The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes \(n=2 \to n=3\) and \(n=4 \to n=6\) transitions, respectively, is
Chemistry
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NEET UG 2025 question paper (official, booklet 45)
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Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and Cl are not the same.
C. Ar, \(\mathrm{K^+}\), \(\mathrm{Cl^-}\), \(\mathrm{Ca^{2+}}\), and \(\mathrm{S^{2-}}\) are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si > Al > Mg > Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below :
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Match List I with List II
List I (Ion): A. \(\mathrm{Co^{2+}}\) B. \(\mathrm{Mg^{2+}}\) C. \(\mathrm{Pb^{2+}}\) D. \(\mathrm{Al^{3+}}\)
List II (Group Number in Cation Analysis): I. Group-I II. Group-III III. Group-IV IV. Group-VI
Choose the correct answer from the options given below :
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Predict the major product 'P' in the following sequence of reactions -
(i) HBr, benzoyl peroxide; (ii) KCN; (iii) Na(Hg)/\(\mathrm{C_2H_5OH}\) -> P (Major), starting from 1-methylcyclopentene
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Energy and radius of first Bohr orbit of \(\mathrm{He^+}\) and \(\mathrm{Li^{2+}}\) are
[Given \(R_H = 2.18\times10^{-18}\) J, \(a_0 = 52.9\) pm]
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Which of the following are paramagnetic?
A. \([\mathrm{NiCl_4}]^{2-}\) B. \(\mathrm{Ni(CO)_4}\) C. \([\mathrm{Ni(CN)_4}]^{2-}\) D. \([\mathrm{Ni(H_2O)_6}]^{2+}\) E. \(\mathrm{Ni(PPh_3)_4}\)
Choose the correct answer from the options given below:
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Given below are two statements :
Statement I : Like nitrogen that can form ammonia, arsenic can form arsine.
Statement II : Antimony cannot form antimony pentoxide.
In the light of the above statements, choose the most appropriate answer from the options given below :
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Which among the following electronic configurations belong to main group elements?
A. \([\mathrm{Ne}]3s^1\) B. \([\mathrm{Ar}]3d^3 4s^2\) C. \([\mathrm{Kr}]4d^{10}5s^2 5p^5\) D. \([\mathrm{Ar}]3d^{10}4s^1\) E. \([\mathrm{Rn}]5f^0 6d^2 7s^2\)
Choose the correct answer from the option given below :
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Dalton's Atomic theory could not explain which of the following?
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Consider the following compounds : \(\underline{\mathrm{K}}\mathrm{O_2}\), \(\mathrm{H_2}\underline{\mathrm{O}}_2\) and \(\mathrm{H_2}\underline{\mathrm{S}}\mathrm{O_4}\).
The oxidation states of the underlined elements in them are, respectively,
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If the half-life (\(t_{1/2}\)) for a first order reaction is 1 minute, then the time required for 99.9% completion of the reaction is closest to :
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The correct order of the wavelength of light absorbed by the following complexes is,
A. \([\mathrm{Co(NH_3)_6}]^{3+}\) B. \([\mathrm{Co(CN)_6}]^{3-}\) C. \([\mathrm{Cu(H_2O)_4}]^{2+}\) D. \([\mathrm{Ti(H_2O)_6}]^{3+}\)
Choose the correct answer from the options given below:
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Which one of the following compounds can exist as cis-trans isomers?
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Phosphoric acid ionizes in three steps with ionization constant values \(K_{a_1}\), \(K_{a_2}\) and \(K_{a_3}\), respectively, while K is the overall ionization constant. Which of the following statements are true?
A. \(\log K = \log K_{a_1} + \log K_{a_2} + \log K_{a_3}\)
B. \(\mathrm{H_3PO_4}\) is a stronger acid than \(\mathrm{H_2PO_4^-}\) and \(\mathrm{HPO_4^{2-}}\).
C. \(K_{a_1} > K_{a_2} > K_{a_3}\)
D. \(K_{a_1} = \frac{K_{a_3}+K_{a_2}}{2}\)
Choose the correct answer from the options given below:
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Which one of the following reactions does NOT give benzene as the product ?
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If the molar conductivity (\(\Lambda_m\)) of a 0.050 mol \(\mathrm{L^{-1}}\) solution of a monobasic weak acid is 90 S \(\mathrm{cm^2\,mol^{-1}}\), its extent (degree) of dissociation will be
[Assume \(\Lambda^\circ_+ = 349.6\) S \(\mathrm{cm^2\,mol^{-1}}\) and \(\Lambda^\circ_- = 50.4\) S \(\mathrm{cm^2\,mol^{-1}}\).]
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Given below are two statements :
Statement I : A hypothetical diatomic molecule with bond order zero is quite stable.
Statement II : As bond order increases, the bond length increases.
In the light of the above statements, choose the most appropriate answer from the options given below :
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Out of the following complex compounds, which of the compound will be having the minimum conductance in solution?
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Match List - I with List - II
List-I: A. \(\mathrm{XeO_3}\) B. \(\mathrm{XeF_2}\) C. \(\mathrm{XeOF_4}\) D. \(\mathrm{XeF_6}\)
List-II: I. \(sp^3d\); linear II. \(sp^3\); pyramidal III. \(sp^3d^3\); distorted octahedral IV. \(sp^3d^2\); square pyramidal
Choose the correct answer from the options given below :
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\(\mathrm{C(s) + 2H_2(g) \to CH_4(g)}\); \(\Delta H = -74.8\) kJ \(\mathrm{mol^{-1}}\)
Which of the following diagrams gives an accurate representation of the above reaction? [R \(\to\) reactants; P \(\to\) products]
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Match List - I with List - II
List-I (Example): A. Humidity B. Alloys C. Amalgams D. Smoke
List-II (Type of Solution): I. Solid in solid II. Liquid in gas III. Solid in gas IV. Liquid in solid
Choose the correct answer from the options given below :
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The correct order of decreasing basic strength of the given amines is :
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Among the following, choose the ones with equal number of atoms.
A. 212 g of \(\mathrm{Na_2CO_3}\) (s) [molar mass = 106 g]
B. 248 g of \(\mathrm{Na_2O}\) (s) [molar mass = 62 g]
C. 240 g of NaOH (s) [molar mass = 40 g]
D. 12 g of \(\mathrm{H_2}\) (g) [molar mass = 2 g]
E. 220 g of \(\mathrm{CO_2}\)(g) [molar mass = 44 g]
Choose the correct answer from the options given below :
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Match List I with List II.
List I (Name of Vitamin): A. Vitamin \(\mathrm{B_{12}}\) B. Vitamin D C. Vitamin \(\mathrm{B_2}\) D. Vitamin \(\mathrm{B_6}\)
List II (Deficiency disease): I. Cheilosis II. Convulsions III. Rickets IV. Pernicious anaemia
Choose the correct answer from the options given below :
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The correct order of decreasing acidity of the following aliphatic acids is :
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Given below are two statements :
Statement I : Ferromagnetism is considered as an extreme form of paramagnetism.
Statement II : The number of unpaired electrons in a \(\mathrm{Cr^{2+}}\) ion (\(Z = 24\)) is the same as that of a \(\mathrm{Nd^{3+}}\) ion (\(Z = 60\)).
In the light of the above statements, choose the correct answer from the options given below :
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Match List I with List II
List I (Mixture): A. \(\mathrm{CHCl_3}\) + \(\mathrm{C_6H_5NH_2}\) B. Crude oil in petroleum industry C. Glycerol from spent-lye D. Aniline - water
List II (Method of Separation): I. Distillation under reduced pressure II. Steam distillation III. Fractional distillation IV. Simple distillation
Choose the correct answer from the options given below :
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For the reaction \(\mathrm{A(g) \rightleftharpoons 2B(g)}\), the backward reaction rate constant is higher than the forward reaction rate constant by a factor of 2500, at 1000 K.
[Given : R = 0.0831 L atm \(\mathrm{mol^{-1}\,K^{-1}}\)]
\(K_p\) for the reaction at 1000 K is
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Given below are two statements :
Statement I : Benzenediazonium salt is prepared by the reaction of aniline with nitrous acid at 273 - 278 K. It decomposes easily in the dry state.
Statement II : Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzenediazonium salt with KI.
In the light of the above statements, choose the most appropriate answer from the options given below :
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How many products (including stereoisomers) are expected from monochlorination of the following compound?
\((\mathrm{CH_3})_2\mathrm{CH-CH_2-CH_3}\)
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Among the given compounds I-III, the correct order of bond dissociation energy of C-H bond marked with * is :
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Which one of the following compounds does not decolourize bromine water?
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The major product of the following reaction is :
Reactant: Ph-CO-CH2CH2-CN; (i) \(\mathrm{CH_3MgBr}\) (excess); (ii) \(\mathrm{H_3O^+}\)
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Which of the following aqueous solution will exhibit highest boiling point?
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Match List - I with List - II
List-I: A. Haber process B. Wacker oxidation C. Wilkinson catalyst D. Ziegler catalyst
List-II: I. Fe catalyst II. \(\mathrm{PdCl_2}\) III. \([(\mathrm{PPh_3})_3\mathrm{RhCl}]\) IV. \(\mathrm{TiCl_4}\) with \(\mathrm{Al(CH_3)_3}\)
Choose the correct answer from the options given below :
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5 moles of liquid X and 10 moles of liquid Y make a solution having a vapour pressure of 70 torr. The vapour pressures of pure X and Y are 63 torr and 78 torr respectively. Which of the following is true regarding the described solution?
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Sugar 'X'
A. is found in honey.
B. is a keto sugar.
C. exists in \(\alpha\) and \(\beta\) - anomeric forms.
D. is laevorotatory.
'X' is :
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Identify the suitable reagent for the following conversion.
Methyl benzoate (Ph-COOCH3) \(\to\) benzaldehyde (Ph-CHO)
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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : (primary alkyl iodide drawn as zig-zag chain ending in I) undergoes \(S_N2\) reaction faster than (the corresponding alkyl chloride, zig-zag chain ending in Cl).
Reason (R) : Iodine is a better leaving group because of its large size.
In the light of the above statements, choose the most appropriate answer from the options given below :
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The standard heat of formation, in kcal/mol of \(\mathrm{Ba^{2+}}\) is :
[Given : standard heat of formation of \(\mathrm{SO_4^{2-}}\) ion (aq) = \(-216\) kcal/mol, standard heat of crystallisation of \(\mathrm{BaSO_4}\)(s) = \(-4.5\) kcal/mol, standard heat of formation of \(\mathrm{BaSO_4}\)(s) = \(-349\) kcal/mol]
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Total number of possible isomers (both structural as well as stereoisomers) of cyclic ethers of molecular formula \(\mathrm{C_4H_8O}\) is :
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Identify the correct orders against the property mentioned :
A. \(\mathrm{H_2O > NH_3 > CHCl_3}\) - dipole moment
B. \(\mathrm{XeF_4 > XeO_3 > XeF_2}\) - number of lone pairs on central atom
C. O-H > C-H > N-O - bond length
D. \(\mathrm{N_2 > O_2 > H_2}\) - bond enthalpy
Choose the correct answer from the options given below :
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Higher yield of NO in \(\mathrm{N_2(g) + O_2(g) \rightleftharpoons 2NO(g)}\) can be obtained at
[\(\Delta H\) of the reaction = + 180.7 kJ \(\mathrm{mol^{-1}}\)]
A. higher temperature
B. lower temperature
C. higher concentration of \(\mathrm{N_2}\)
D. higher concentration of \(\mathrm{O_2}\)
Choose the correct answer from the options given below:
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If the rate constant of a reaction is 0.03 \(\mathrm{s^{-1}}\), how much time does it take for 7.2 mol \(\mathrm{L^{-1}}\) concentration of the reactant to get reduced to 0.9 mol \(\mathrm{L^{-1}}\)?
(Given: log 2 = 0.301)
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Which one of the following reactions does NOT belong to "Lassaigne's test"?
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Given below are two statements:
Statement I : Aniline does not undergo Friedel-Crafts alkylation reaction.
Statement II : Aniline cannot be prepared through Gabriel synthesis.
In the light of the above statements, choose the correct answer from the options given below:
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Match List I with List II.
List I (Compound): A. \(NH_3\) B. \(BrF_5\) C. \(XeF_4\) D. \(SF_6\)
List II (Shape/geometry): I. Trigonal Pyramidal II. Square Planar III. Octahedral IV. Square Pyramidal
Choose the correct answer from the options given below:
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Match List I with List II.
List I (Molecule): A. ethane B. ethene C. carbon molecule, \(C_2\) D. ethyne
List II (Number and types of bond/s between two carbon atoms): I. one \(\sigma\)-bond and two \(\pi\)-bonds II. two \(\pi\)-bonds III. one \(\sigma\)-bond IV. one \(\sigma\)-bond and one \(\pi\)-bond
Choose the correct answer from the options given below:
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For the reaction \(2A \rightleftharpoons B + C\), \(K_c = 4\times10^{-3}\). At a given time, the composition of reaction mixture is : \([A]=[B]=[C]=2\times10^{-3}\) M.
Then, which of the following is correct?
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Match List I with List II.
List I (Process): A. Isothermal process B. Isochoric process C. Isobaric process D. Adiabatic process
List II (Conditions): I. No heat exchange II. Carried out at constant temperature III. Carried out at constant volume IV. Carried out at constant pressure
Choose the correct answer from the options given below:
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Match List I with List II.
List I (Quantum Number): A. \(m_l\) B. \(m_s\) C. \(l\) D. \(n\)
List II (Information provided): I. shape of orbital II. size of orbital III. orientation of orbital IV. orientation of spin of electron
Choose the correct answer from the options given below:
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Arrange the following elements in increasing order of first ionization enthalpy:
Li, Be, B, C, N
Choose the correct answer from the options given below:
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Among Group 16 elements, which one does NOT show \(-2\) oxidation state?
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In which of the following equilibria, \(K_p\) and \(K_c\) are NOT equal?
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The reagents with which glucose does not react to give the corresponding tests/products are
A. Tollen's reagent B. Schiff's reagent C. HCN D. \(NH_2OH\) E. \(NaHSO_3\)
Choose the correct options from the given below:
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Identify the correct reagents that would bring about the following transformation.
[structure transformation shown in figure: ring-CH\(_2\)-CH=CH\(_2\) \(\rightarrow\) ring-CH\(_2\)-CH\(_2\)-CHO]
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The \(E^\circ\) value for the \(Mn^{3+}/Mn^{2+}\) couple is more positive than that of \(Cr^{3+}/Cr^{2+}\) or \(Fe^{3+}/Fe^{2+}\) due to change of
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Given below are two statements :
Statement I : Both \([Co(NH_3)_6]^{3+}\) and \([CoF_6]^{3-}\) complexes are octahedral but differ in their magnetic behaviour.
Statement II : \([Co(NH_3)_6]^{3+}\) is diamagnetic whereas \([CoF_6]^{3-}\) is paramagnetic.
In the light of the above statements, choose the correct answer from the options given below:
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Fehling's solution 'A' is
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In which of the following processes entropy increases?
A. A liquid evaporates to vapour.
B. Temperature of a crystalline solid lowered from 130 K to 0 K.
C. \(2NaHCO_{3(s)} \rightarrow Na_2CO_{3(s)} + CO_{2(g)} + H_2O_{(g)}\)
D. \(Cl_{2(g)} \rightarrow 2Cl_{(g)}\)
Choose the correct answer from the options given below:
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The energy of an electron in the ground state (n = 1) for \(He^+\) ion is \(-x\) J, then that for an electron in n = 2 state for \(Be^{3+}\) ion in J is :
-
Match List I with List II.
List I (Reactions): A. [structure: bicyclohexylidene \(\rightarrow\) 2 cyclohexanone] B. [structure: benzene \(\rightarrow\) benzophenone] C. [structure: cyclohexanol \(\rightarrow\) cyclohexanone] D. [structure: ethylbenzene \(\rightarrow\) potassium benzoate]
List II (Reagents/Condition): I. benzoyl chloride / Anhyd. \(AlCl_3\) II. \(CrO_3\) III. \(KMnO_4\)/KOH, \(\Delta\) IV. (i) \(O_3\) (ii) \(Zn\)-\(H_2O\)
Choose the correct answer from the options given below:
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Activation energy of any chemical reaction can be calculated if one knows the value of
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The most stable carbocation among the following is:
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Given below are two statements:
Statement I : The boiling point of three isomeric pentanes follows the order
n-pentane > isopentane > neopentane
Statement II : When branching increases, the molecule attains a shape of sphere. This results in smaller surface area for contact, due to which the intermolecular forces between the spherical molecules are weak, thereby lowering the boiling point.
In the light of the above statements, choose the most appropriate answer from the options given below:
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Which one of the following alcohols reacts instantaneously with Lucas reagent?
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The Henry's law constant (\(K_H\)) values of three gases (A, B, C) in water are 145, \(2\times10^{-5}\) and 35 kbar, respectively. The solubility of these gases in water follow the order:
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Which plot of ln k vs \(\frac{1}{T}\) is consistent with Arrhenius equation?
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On heating, some solid substances change from solid to vapour state without passing through liquid state. The technique used for the purification of such solid substances based on the above principle is known as
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Intramolecular hydrogen bonding is present in
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1 gram of sodium hydroxide was treated with 25 mL of 0.75 M HCl solution, the mass of sodium hydroxide left unreacted is equal to
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Which reaction is NOT a redox reaction?
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'Spin only' magnetic moment is same for which of the following ions?
A. \(Ti^{3+}\) B. \(Cr^{2+}\) C. \(Mn^{2+}\) D. \(Fe^{2+}\) E. \(Sc^{3+}\)
Choose the most appropriate answer from the options given below:
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The highest number of helium atoms is in
-
Match List I with List II.
List I (Complex): A. \([Co(NH_3)_5(NO_2)]Cl_2\) B. \([Co(NH_3)_5(SO_4)]Br\) C. \([Co(NH_3)_6][Cr(CN)_6]\) D. \([Co(H_2O)_6]Cl_3\)
List II (Type of isomerism): I. Solvate isomerism II. Linkage isomerism III. Ionization isomerism IV. Coordination isomerism
Choose the correct answer from the options given below:
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Given below are two statements:
Statement I : The boiling point of hydrides of Group 16 elements follow the order
\(H_2O > H_2Te > H_2Se > H_2S\).
Statement II : On the basis of molecular mass, \(H_2O\) is expected to have lower boiling point than the other members of the group but due to the presence of extensive H-bonding in \(H_2O\), it has higher boiling point.
In the light of the above statements, choose the correct answer from the options given below:
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A compound with a molecular formula of \(C_6H_{14}\) has two tertiary carbons. Its IUPAC name is:
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Match List I with List II.
List I (Conversion): A. 1 mol of \(H_2O\) to \(O_2\) B. 1 mol of \(MnO_4^-\) to \(Mn^{2+}\) C. 1.5 mol of Ca from molten \(CaCl_2\) D. 1 mol of FeO to \(Fe_2O_3\)
List II (Number of Faraday required): I. 3F II. 2F III. 1F IV. 5F
Choose the correct answer from the options given below:
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The compound that will undergo \(S_N1\) reaction with the fastest rate is
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Arrange the following elements in increasing order of electronegativity:
N, O, F, C, Si
Choose the correct answer from the options given below:
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Major products A and B formed in the following reaction sequence, are
[scheme: 2-methylcyclohexanol (OH and \(H_3C\) on adjacent ring carbons) \(\xrightarrow{PBr_3}\) A (major) \(\xrightarrow[\Delta]{alc.\ KOH}\) B (major), see figure]
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Identify the correct answer.
-
The work done during reversible isothermal expansion of one mole of hydrogen gas at 25\(^\circ\)C from pressure of 20 atmosphere to 10 atmosphere is:
(Given R = 2.0 cal \(K^{-1}\) \(mol^{-1}\))
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Consider the following reaction in a sealed vessel at equilibrium with concentrations of \(N_2 = 3.0\times10^{-3}\) M, \(O_2 = 4.2\times10^{-3}\) M and \(NO = 2.8\times10^{-3}\) M.
\(2NO_{(g)} \rightleftharpoons N_{2(g)} + O_{2(g)}\)
If 0.1 mol \(L^{-1}\) of \(NO_{(g)}\) is taken in a closed vessel, what will be degree of dissociation (\(\alpha\)) of \(NO_{(g)}\) at equilibrium?
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For the given reaction:
[scheme: ring-C(H)=CH-ring \(\xrightarrow{KMnO_4/H^+}\) 'P' (major product), see figure]
'P' is
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The pair of lanthanoid ions which are diamagnetic is
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The products A and B obtained in the following reactions, respectively, are
\(3ROH + PCl_3 \rightarrow 3RCl + A\)
\(ROH + PCl_5 \rightarrow RCl + HCl + B\)
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Given below are certain cations. Using inorganic qualitative analysis, arrange them in increasing group number from 0 to VI.
A. \(Al^{3+}\) B. \(Cu^{2+}\) C. \(Ba^{2+}\) D. \(Co^{2+}\) E. \(Mg^{2+}\)
Choose the correct answer from the options given below:
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Given below are two statements :
Statement I : \([Co(NH_3)_6]^{3+}\) is a homoleptic complex whereas \([Co(NH_3)_4Cl_2]^+\) is a heteroleptic complex.
Statement II : Complex \([Co(NH_3)_6]^{3+}\) has only one kind of ligands but \([Co(NH_3)_4Cl_2]^+\) has more than one kind of ligands.
In the light of the above statements, choose the correct answer from the options given below:
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A compound X contains 32% of A, 20% of B and remaining percentage of C. Then, the empirical formula of X is :
(Given atomic masses of A = 64; B = 40; C = 32 u)
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The plot of osmotic pressure (\(\Pi\)) vs concentration (mol \(L^{-1}\)) for a solution gives a straight line with slope 25.73 L bar \(mol^{-1}\). The temperature at which the osmotic pressure measurement is done is:
(Use R = 0.083 L bar \(mol^{-1}\) \(K^{-1}\))
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Identify the major product C formed in the following reaction sequence :
\(CH_3-CH_2-CH_2-I \xrightarrow{NaCN} A \xrightarrow[\text{Partial hydrolysis}]{OH^-} B \xrightarrow[Br_2]{NaOH} C\) (major)
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During the preparation of Mohr's salt solution (Ferrous ammonium sulphate), which of the following acid is added to prevent hydrolysis of \(Fe^{2+}\) ion?
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The rate of a reaction quadruples when temperature changes from 27\(^\circ\)C to 57\(^\circ\)C. Calculate the energy of activation.
Given R = 8.314 J \(K^{-1}\) \(mol^{-1}\), log 4 = 0.6021
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Mass in grams of copper deposited by passing 9.6487 A current through a voltmeter containing copper sulphate solution for 100 seconds is:
(Given : Molar mass of Cu : 63 g \(mol^{-1}\), 1F = 96487 C)
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Taking stability as the factor, which one of the following represents correct relationship?
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Identify the product in the following reaction :
Benzenediazonium chloride (\(\mathrm{C_6H_5N_2^+Cl^-}\)) with (i) Cu\(_2\)Br\(_2\)/HBr (ii) Mg/dry ether (iii) H\(_2\)O \(\rightarrow\) Product
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The given compound
\(\mathrm{C_6H_5-CH=CH-CH(X)-CH_2CH_3}\) (benzene ring attached to CH=CH-CH(X)-CH\(_2\)CH\(_3\))
is an example of ________.
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In Lassaigne's extract of an organic compound, both nitrogen and sulphur are present, which gives blood red colour with Fe\(^{3+}\) due to the formation of -
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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : A reaction can have zero activation energy.
Reasons R : The minimum extra amount of energy absorbed by reactant molecules so that their energy becomes equal to threshold value, is called activation energy.
In the light of the above statements, choose the correct answer from the options given below :
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The right option for the mass of CO\(_2\) produced by heating 20 g of 20% pure limestone is (Atomic mass of Ca = 40)
\(\mathrm{CaCO_3 \xrightarrow{1200\ K} CaO + CO_2}\)
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Complete the following reaction :
cyclohexanone [A] \(\xrightarrow{HCN}\) cyclohexanone cyanohydrin (1-hydroxycyclohexanecarbonitrile) [B] \(\xrightarrow[\Delta]{conc.\ H_2SO_4}\) [C]
[C] is ________.
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Given below are two statements :
Statement I : A unit formed by the attachment of a base to 1' position of sugar is known as nucleoside
Statement II : When nucleoside is linked to phosphorous acid at 5'-position of sugar moiety, we get nucleotide.
In the light of the above statements, choose the correct answer from the options given below :
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A compound is formed by two elements A and B. The element B forms cubic close packed structure and atoms of A occupy 1/3 of tetrahedral voids. If the formula of the compound is A\(_x\)B\(_y\), then the value of x + y is in option
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The stability of Cu\(^{2+}\) is more than Cu\(^+\) salts in aqueous solution due to -
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Match List - I with List - II :
List - I: A. Coke B. Diamond C. Fullerene D. Graphite
List - II: I. Carbon atoms are sp\(^3\) hybridised. II. Used as a dry lubricant III. Used as a reducing agent IV. Cage like molecules
Choose the correct answer from the options given below :
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Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : Helium is used to dilute oxygen in diving apparatus.
Reasons R : Helium has high solubility in O\(_2\).
In the light of the above statements, choose the correct answer from the options given below :
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Some tranquilizers are listed below. Which one from the following belongs to barbiturates?
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Which of the following statements are NOT correct?
A. Hydrogen is used to reduce heavy metal oxides to metals.
B. Heavy water is used to study reaction mechanism.
C. Hydrogen is used to make saturated fats from oils.
D. The H-H bond dissociation enthalpy is lowest as compared to a single bond between two atoms of any element.
E. Hydrogen reduces oxides of metals that are more active than iron.
Choose the most appropriate answer from the options given below :
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For a certain reaction, the rate = k[A]\(^2\)[B], when the initial concentration of A is tripled keeping concentration of B constant, the initial rate would
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Which one is an example of heterogenous catalysis?
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Which one of the following statements is correct?
-
Weight (g) of two moles of the organic compound, which is obtained by heating sodium ethanoate with sodium hydroxide in presence of calcium oxide is :
-
The element expected to form largest ion to achieve the nearest noble gas configuration is :
-
The correct order of energies of molecular orbitals of N\(_2\) molecule, is :
-
Homoleptic complex from the following complexes is :
-
Intermolecular forces are forces of attraction and repulsion between interacting particles that will include :
A. dipole - dipole forces.
B. dipole - induced dipole forces.
C. hydrogen bonding.
D. covalent bonding.
E. dispersion forces.
Choose the most appropriate answer from the options given below :
-
The number of \(\sigma\) bonds, \(\pi\) bonds and lone pair of electrons in pyridine, respectively are :
-
Select the correct statements from the following :
A. Atoms of all elements are composed of two fundamental particles.
B. The mass of the electron is \(9.10939 \times 10^{-31}\) kg.
C. All the isotopes of a given element show same chemical properties.
D. Protons and electrons are collectively known as nucleons.
E. Dalton's atomic theory, regarded the atom as an ultimate particle of matter.
Choose the correct answer from the options given below :
-
Identify product (A) in the following reaction :
3-(3-acetylphenyl)-substituted cyclohexyl methyl ketone: a cyclohexane ring bearing an acetyl group, joined to a benzene ring bearing an acetyl group (meta), \(\xrightarrow[\text{conc. HCl}]{\text{Zn-Hg}}\) (A) + 2H\(_2\)O
-
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : In equation \(\Delta_r G = -nFE_{cell}\), value of \(\Delta_r G\) depends on n.
Reasons R : \(E_{cell}\) is an intensive property and \(\Delta_r G\) is an extensive property.
In the light of the above statements, choose the correct answer from the options given below :
-
Which amongst the following options is correct graphical representation of Boyle's Law?
(1) P vs T, straight lines through origin labelled V\(_1\), V\(_2\), V\(_3\) with V\(_1\)<V\(_2\)<V\(_3\); (2) P vs V, hyperbolas labelled T\(_1\), T\(_2\), T\(_3\) with T\(_3\)>T\(_2\)>T\(_1\); (3) P vs 1/V, straight lines labelled T\(_3\), T\(_2\), T\(_1\) with T\(_3\)>T\(_2\)>T\(_1\); (4) P vs 1/V, hyperbolic curves labelled T\(_3\), T\(_2\), T\(_1\) with T\(_3\)>T\(_2\)>T\(_1\).
-
The relation between n\(_m\), (n\(_m\) = the number of permissible values of magnetic quantum number (m)) for a given value of azimuthal quantum number (\(l\)), is
-
The conductivity of centimolar solution of KCl at 25°C is 0.0210 ohm\(^{-1}\) cm\(^{-1}\) and the resistance of the cell containing the solution at 25°C is 60 ohm. The value of cell constant is -
-
Consider the following reaction and identify the product (P).
\(\mathrm{CH_3-CH(CH_3)-CH(OH)-CH_3}\) (3 - Methylbutan-2-ol) \(\xrightarrow{HBr}\) Product (P)
-
Which amongst the following molecules on polymerization produces neoprene?
-
Amongst the following, the total number of species NOT having eight electrons around central atom in its outer most shell, is
NH\(_3\), AlCl\(_3\), BeCl\(_2\), CCl\(_4\), PCl\(_5\) :
-
Amongst the given options which of the following molecules / ion acts as a Lewis acid?
-
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : Metallic sodium dissolves in liquid ammonia giving a deep blue solution, which is paramagnetic.
Reasons R : The deep blue solution is due to the formation of amide.
In the light of the above statements, choose the correct answer from the options given below :
-
Which of the following reactions will NOT give primary amine as the product?
-
Which of the following statements are INCORRECT?
A. All the transition metals except scandium form MO oxides which are ionic.
B. The highest oxidation number corresponding to the group number in transition metal oxides is attained in Sc\(_2\)O\(_3\) to Mn\(_2\)O\(_7\).
C. Basic character increases from V\(_2\)O\(_3\) to V\(_2\)O\(_4\) to V\(_2\)O\(_5\).
D. V\(_2\)O\(_4\) dissolves in acids to give VO\(_4^{3-}\) salts.
E. CrO is basic but Cr\(_2\)O\(_3\) is amphoteric.
Choose the correct answer from the options given below :
-
Consider the following reaction :
\(\mathrm{C_6H_5-CH_2-O-C_6H_5 \xrightarrow[\Delta]{HI} A + B}\) (benzyl phenyl ether)
Identify products A and B.
-
Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?
-
What fraction of one edge centred octahedral void lies in one unit cell of fcc?
-
Given below are two statements :
Statement I : The nutrient deficient water bodies lead to eutrophication.
Statement II : Eutrophication leads to decrease in the level of oxygen in the water bodies.
In the light of the above statements, choose the correct answer from the options given below :
-
Which amongst the following will be most readily dehydrated under acidic conditions ?
-
Match List - I with List - II :
List - I (Oxoacids of Sulphur): A. Peroxodisulphuric acid B. Sulphuric acid C. Pyrosulphuric acid D. Sulphurous acid
List - II (Bonds): I. Two S-OH, Four S=O, One S-O-S II. Two S-OH, One S=O III. Two S-OH, Four S=O, One S-O-O-S IV. Two S-OH, Two S=O
Choose the correct answer from the options given below :
-
Identify the major product obtained in the following reaction :
2-acetylbenzaldehyde (benzene ring with ortho -COCH\(_3\) and -CHO) + 2\([\mathrm{Ag(NH_3)_2}]^+\) + 3 \(^-\)OH \(\xrightarrow{\Delta}\) major product
-
Identify the final product [D] obtained in the following sequence of reactions.
\(\mathrm{CH_3CHO \xrightarrow[ii)\ H_3O^+]{i)\ LiAlH_4} [A] \xrightarrow[\Delta]{H_2SO_4} [B] \xrightarrow{HBr} [C]}\), then [C] + bromobenzene \(\xrightarrow{Na/dry\ ether}\) [D]
-
The reaction that does NOT take place in a blast furnace between 900 K to 1500 K temperature range during extraction of iron is :
-
Pumice stone is an example of -
-
Which complex compound is most stable?
-
Consider the following compounds/species :
i. naphthalene ii. cyclopentadienyl anion iii. cyclobutadiene iv. cyclopropenyl anion v. cyclopropenyl cation vi. cyclooctatetraene vii. anthracene (all drawn as structures)
The number of compounds/species which obey Huckel's rule is ________.
-
The equilibrium concentrations of the species in the reaction A + B \(\rightleftharpoons\) C + D are 2, 3, 10 and 6 mol L\(^{-1}\), respectively at 300 K. \(\Delta G^\circ\) for the reaction is (R = 2 cal / mol K)
-
On balancing the given redox reaction,
\(a\,\mathrm{Cr_2O_7^{2-}} + b\,\mathrm{SO_3^{2-}(aq)} + c\,\mathrm{H^+(aq)} \rightarrow 2a\,\mathrm{Cr^{3+}(aq)} + b\,\mathrm{SO_4^{2-}(aq)} + \dfrac{c}{2}\mathrm{H_2O}(\ell)\)
the coefficients a, b and c are found to be, respectively -
NEET UG 2022 question paper (official, booklet R6)
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Which statement regarding polymers is not correct ?
-
At 298 K, the standard electrode potentials of \(Cu^{2+}/Cu\), \(Zn^{2+}/Zn\), \(Fe^{2+}/Fe\) and \(Ag^+/Ag\) are 0.34 V, \(-0.76\) V, \(-0.44\) V and 0.80 V, respectively.
On the basis of standard electrode potential, predict which of the following reaction can not occur ?
-
The IUPAC name of an element with atomic number 119 is
-
Given below are two statements :
Statement I :
In the coagulation of a negative sol, the flocculating power of the three given ions is in the order -
\(Al^{3+} > Ba^{2+} > Na^+\)
Statement II :
In the coagulation of a positive sol, the flocculating power of the three given salts is in the order -
\(NaCl > Na_2SO_4 > Na_3PO_4\)
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Which of the following statement is not correct about diborane ?
-
\(RMgX + CO_2 \xrightarrow{\text{dry ether}} Y \xrightarrow{H_3O^+} RCOOH\)
What is Y in the above reaction ?
-
What mass of 95% pure \(CaCO_3\) will be required to neutralise 50 mL of 0.5 M HCl solution according to the following reaction ?
\(CaCO_{3(s)} + 2HCl_{(aq)} \to CaCl_{2(aq)} + CO_{2(g)} + 2H_2O_{(l)}\)
[Calculate upto second place of decimal point]
-
Which amongst the following is incorrect statement ?
-
Amongst the following which one will have maximum 'lone pair - lone pair' electron repulsions ?
-
Choose the correct statement :
-
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) :
In a particular point defect, an ionic solid is electrically neutral, even if few of its cations are missing from its unit cells.
Reason (R) :
In an ionic solid, Frenkel defect arises due to dislocation of cation from its lattice site to interstitial site, maintaining overall electrical neutrality.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Match List - I with List - II.
List - I: (a) Li (b) Na (c) KOH (d) Cs
List - II: (i) absorbent for carbon dioxide (ii) electrochemical cells (iii) coolant in fast breeder reactors (iv) photoelectric cell
Choose the correct answer from the options given below :
-
Given below are half cell reactions :
\(MnO_4^- + 8H^+ + 5e^- \to Mn^{2+} + 4H_2O\),
\(E^\circ_{Mn^{2+}/MnO_4^-} = -1.510\) V
\(\frac{1}{2}O_2 + 2H^+ + 2e^- \to H_2O\),
\(E^\circ_{O_2/H_2O} = +1.223\) V
Will the permanganate ion, \(MnO_4^-\) liberate \(O_2\) from water in the presence of an acid ?
-
Match List - I with List - II.
List - I (Hydrides): (a) \(MgH_2\) (b) \(GeH_4\) (c) \(B_2H_6\) (d) HF
List - II (Nature): (i) Electron precise (ii) Electron deficient (iii) Electron rich (iv) Ionic
Choose the correct answer from the options given below :
-
Given below are two statements :
Statement I :
The acidic strength of monosubstituted nitrophenol is higher than phenol because of electron withdrawing nitro group.
Statement II :
\(o\)-nitrophenol, \(m\)-nitrophenol and \(p\)-nitrophenol will have same acidic strength as they have one nitro group attached to the phenolic ring.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Match List - I with List - II.
List - I (Drug class): (a) Antacids (b) Antihistamines (c) Analgesics (d) Antimicrobials
List - II (Drug molecule): (i) Salvarsan (ii) Morphine (iii) Cimetidine (iv) Seldane
Choose the correct answer from the options given below :
-
The incorrect statement regarding enzymes is :
-
Identify the incorrect statement from the following.
-
The incorrect statement regarding chirality is :
-
Which compound amongst the following is not an aromatic compound ?
-
The given graph is a representation of kinetics of a reaction.
[Graph: y versus x at constant temperature T]
The \(y\) and \(x\) axes for zero and first order reactions, respectively are
-
Which one is not correct mathematical equation for Dalton's Law of partial pressure ? Here \(p\) = total pressure of gaseous mixture
-
Given below are two statements :
Statement I :
Primary aliphatic amines react with \(HNO_2\) to give unstable diazonium salts.
Statement II :
Primary aromatic amines react with \(HNO_2\) to form diazonium salts which are stable even above 300 K.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Identify the incorrect statement from the following
-
The IUPAC name of the complex -
\([Ag(H_2O)_2][Ag(CN)_2]\) is :
-
The pH of the solution containing 50 mL each of 0.10 M sodium acetate and 0.01 M acetic acid is
[Given \(pK_a\) of \(CH_3COOH\) = 4.57]
-
Which of the following p-V curve represents maximum work done ?
-
Match List - I with List - II.
List - I (Products formed): (a) Cyanohydrin (b) Acetal (c) Schiff's base (d) Oxime
List - II (Reaction of carbonyl compound with): (i) \(NH_2OH\) (ii) \(RNH_2\) (iii) alcohol (iv) HCN
Choose the correct answer from the options given below :
-
Which of the following sequence of reactions is suitable to synthesize chlorobenzene ?
-
The Kjeldahl's method for the estimation of nitrogen can be used to estimate the amount of nitrogen in which one of the following compounds ?
-
Given below are two statements :
Statement I :
The boiling points of aldehydes and ketones are higher than hydrocarbons of comparable molecular masses because of weak molecular association in aldehydes and ketones due to dipole - dipole interactions.
Statement II :
The boiling points of aldehydes and ketones are lower than the alcohols of similar molecular masses due to the absence of H-bonding.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Given below are two statements :
Statement I :
The boiling points of the following hydrides of group 16 elements increases in the order -
\(H_2O < H_2S < H_2Se < H_2Te\).
Statement II :
The boiling points of these hydrides increase with increase in molar mass.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
In one molal solution that contains 0.5 mole of a solute, there is
-
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : ICl is more reactive than \(I_2\).
Reason (R) : I-Cl bond is weaker than I-I bond.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
Gadolinium has a low value of third ionisation enthalpy because of
-
Compound X on reaction with \(O_3\) followed by Zn/\(H_2O\) gives formaldehyde and 2-methyl propanal as products. The compound X is :
-
For a first order reaction A \(\to\) Products, initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for the reaction in \(min^{-1}\) is
-
In the neutral or faintly alkaline medium, \(KMnO_4\) oxidises iodide into iodate. The change in oxidation state of manganese in this reaction is from
-
A 10.0 L flask contains 64 g of oxygen at 27°C. (Assume \(O_2\) gas is behaving ideally). The pressure inside the flask in bar is
(Given R = 0.0831 L bar \(K^{-1}\) \(mol^{-1}\))
-
Given below are two statements :
Statement I :
In Lucas test, primary, secondary and tertiary alcohols are distinguished on the basis of their reactivity with conc. HCl + \(ZnCl_2\), known as Lucas Reagent.
Statement II :
Primary alcohols are most reactive and immediately produce turbidity at room temperature on reaction with Lucas Reagent.
In the light of the above statements, choose the most appropriate answer from the options given below :
-
\(3O_2(g) \rightleftharpoons 2O_3(g)\)
for the above reaction at 298 K, \(K_c\) is found to be \(3.0 \times 10^{-59}\). If the concentration of \(O_2\) at equilibrium is 0.040 M then concentration of \(O_3\) in M is
-
Match List - I with List - II.
List - I (Ores): (a) Haematite (b) Magnetite (c) Calamine (d) Kaolinite
List - II (Composition): (i) \(Fe_3O_4\) (ii) \(ZnCO_3\) (iii) \(Fe_2O_3\) (iv) \([Al_2(OH)_4Si_2O_5]\)
Choose the correct answer from the options given below :
-
Copper crystallises in fcc unit cell with cell edge length of \(3.608 \times 10^{-8}\) cm. The density of copper is 8.92 g \(cm^{-3}\). Calculate the atomic mass of copper.
-
The correct IUPAC name of the following compound is :
[skeletal structure with Cl, OH, Br and a methyl branch]
-
Find the emf of the cell in which the following reaction takes place at 298 K
\(Ni(s) + 2Ag^+ (0.001\ M) \to Ni^{2+} (0.001\ M) + 2Ag(s)\)
(Given that \(E^\circ_{cell} = 10.5\) V, \(\frac{2.303\,RT}{F} = 0.059\) at 298 K)
-
The order of energy absorbed which is responsible for the color of complexes
(A) \([Ni(H_2O)_2(en)_2]^{2+}\)
(B) \([Ni(H_2O)_4(en)]^{2+}\) and
(C) \([Ni(en)_3]^{2+}\)
is
-
Which one of the following is not formed when acetone reacts with 2-pentanone in the presence of dilute NaOH followed by heating ?
-
If radius of second Bohr orbit of the \(He^+\) ion is 105.8 pm, what is the radius of third Bohr orbit of \(Li^{2+}\) ion ?
-
The pollution due to oxides of sulphur gets enhanced due to the presence of :
(a) particulate matter
(b) ozone
(c) hydrocarbons
(d) hydrogen peroxide
Choose the most appropriate answer from the options given below :
-
The product formed from the following reaction sequence is
[benzonitrile] \(\xrightarrow[\text{(iii) } H_2O]{\text{(i) } LiAlH_4, H_2O;\ \text{(ii) } NaNO_2 + HCl}\)
NEET UG 2021 question paper (official, booklet M4)
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Which one among the following is the correct option for right relationship between \(C_P\) and \(C_V\) for one mole of ideal gas ?
-
The correct option for the number of body centred unit cells in all 14 types of Bravais lattice unit cells is :
-
Noble gases are named because of their inertness towards reactivity. Identify an incorrect statement about them.
-
The major product formed in dehydrohalogenation reaction of 2-Bromo pentane is Pent-2-ene. This product formation is based on ?
-
The compound which shows metamerism is :
-
\(BF_3\) is planar and electron deficient compound. Hybridization and number of electrons around the central atom, respectively are :
-
The right option for the statement "Tyndall effect is exhibited by", is :
-
Among the following alkaline earth metal halides, one which is covalent and soluble in organic solvents is :
-
Which one of the following methods can be used to obtain highly pure metal which is liquid at room temperature ?
-
For a reaction A\(\rightarrow\)B, enthalpy of reaction is \(-4.2\) kJ mol\(^{-1}\) and enthalpy of activation is 9.6 kJ mol\(^{-1}\). The correct potential energy profile for the reaction is shown in option.
-
Which one of the following polymers is prepared by addition polymerisation ?
-
The major product of the following chemical reaction is :
\((CH_3)_2CH-CH=CH_2 + HBr \xrightarrow{(C_6H_5CO)_2O_2} ?\)
-
Choose the correct option for graphical representation of Boyle's law, which shows a graph of pressure vs. volume of a gas at different temperatures :
-
Dihedral angle of least stable conformer of ethane is :
-
An organic compound contains 78% (by wt.) carbon and remaining percentage of hydrogen. The right option for the empirical formula of this compound is : [Atomic wt. of C is 12, H is 1]
-
The maximum temperature that can be achieved in blast furnace is :
-
The following solutions were prepared by dissolving 10 g of glucose (\(C_6H_{12}O_6\)) in 250 ml of water (\(P_1\)), 10 g of urea (\(CH_4N_2O\)) in 250 ml of water (\(P_2\)) and 10 g of sucrose (\(C_{12}H_{22}O_{11}\)) in 250 ml of water (\(P_3\)). The right option for the decreasing order of osmotic pressure of these solutions is :
-
Zr (Z=40) and Hf (Z=72) have similar atomic and ionic radii because of :
-
The molar conductance of NaCl, HCl and \(CH_3COONa\) at infinite dilution are 126.45, 426.16 and 91.0 S cm\(^2\) mol\(^{-1}\) respectively. The molar conductance of \(CH_3COOH\) at infinite dilution is. Choose the right option for your answer.
-
Right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell are :
-
A particular station of All India Radio, New Delhi, broadcasts on a frequency of 1,368 kHz (kilohertz). The wavelength of the electromagnetic radiation emitted by the transmitter is : [speed of light, c=\(3.0\times10^8\) ms\(^{-1}\)]
-
Ethylene diaminetetraacetate (EDTA) ion is :
-
The correct sequence of bond enthalpy of 'C–X' bond is :
-
The \(pK_b\) of dimethylamine and \(pK_a\) of acetic acid are 3.27 and 4.77 respectively at T (K). The correct option for the pH of dimethylammonium acetate solution is :
-
The structures of beryllium chloride in solid state and vapour phase, are :
-
Given below are two statements :
Statement I : Aspirin and Paracetamol belong to the class of narcotic analgesics.
Statement II : Morphine and Heroin are non-narcotic analgesics.
In the light of the above statements, choose the correct answer from the options given below.
-
Match List - I with List - II.
List - I : (a) \(PCl_5\) (b) \(SF_6\) (c) \(BrF_5\) (d) \(BF_3\)
List - II : (i) Square pyramidal (ii) Trigonal planar (iii) Octahedral (iv) Trigonal bipyramidal
Choose the correct answer from the options given below.
-
Statement I : Acid strength increases in the order given as HF << HCl << HBr << HI.
Statement II : As the size of the elements F, Cl, Br, I increases down the group, the bond strength of HF, HCl, HBr and HI decreases and so the acid strength increases.
In the light of the above statements, choose the correct answer from the options given below.
-
Identify the compound that will react with Hinsberg's reagent to give a solid which dissolves in alkali.
-
What is the IUPAC name of the organic compound formed in the following chemical reaction ?
Acetone \(\xrightarrow[\text{(ii) } H_2O, H^+]{\text{(i) } C_2H_5MgBr,\ \text{dry Ether}}\) Product
-
Which of the following reactions is the metal displacement reaction ? Choose the right option.
-
The correct structure of 2,6-Dimethyl-dec-4-ene is :
-
The incorrect statement among the following is :
-
The RBC deficiency is deficiency disease of :
-
Tritium, a radioactive isotope of hydrogen, emits which of the following particles ?
-
Match List - I with List - II.
List - I : (a) \(2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)\) (b) \(HOCl(g) \xrightarrow{h\nu} \dot{O}H + \dot{C}l\) (c) \(CaCO_3 + H_2SO_4 \rightarrow CaSO_4 + H_2O + CO_2\) (d) \(NO_2(g) \xrightarrow{h\nu} NO(g) + O(g)\)
List - II : (i) Acid rain (ii) Smog (iii) Ozone depletion (iv) Tropospheric pollution
Choose the correct answer from the options given below.
-
\(CH_3CH_2COO^-Na^+ \xrightarrow[\text{Heat}]{NaOH,\ +\ ?} CH_3CH_3 + Na_2CO_3\).
Consider the above reaction and identify the missing reagent/chemical.
-
The product formed in the following chemical reaction is :
2-(methyl-substituted) cyclohexanone bearing \(CH_2-C(=O)-OCH_3\) and \(CH_3\) groups \(\xrightarrow[C_2H_5OH]{NaBH_4}\) ?
-
Match List - I with List - II.
List - I : (a) \([Fe(CN)_6]^{3-}\) (b) \([Fe(H_2O)_6]^{3+}\) (c) \([Fe(CN)_6]^{4-}\) (d) \([Fe(H_2O)_6]^{2+}\)
List - II : (i) 5.92 BM (ii) 0 BM (iii) 4.90 BM (iv) 1.73 BM
Choose the correct answer from the options given below.
-
From the following pairs of ions which one is not an iso-electronic pair ?
-
The reagent 'R' in the given sequence of chemical reaction is :
2,4,6-tribromoaniline \(\xrightarrow{NaNO_2, HCl,\ 0-5^\circ C}\) 2,4,6-tribromobenzenediazonium chloride \(\xrightarrow{R}\) 1,3,5-tribromobenzene
-
Choose the correct option for the total pressure (in atm.) in a mixture of 4 g \(O_2\) and 2 g \(H_2\) confined in a total volume of one litre at \(0^\circ C\) is :
[Given R=0.082 L atm mol\(^{-1}\)K\(^{-1}\), T=273 K]
-
Which of the following molecules is non-polar in nature ?
-
In which one of the following arrangements the given sequence is not strictly according to the properties indicated against it ?
-
The correct option for the value of vapour pressure of a solution at \(45^\circ C\) with benzene to octane in molar ratio 3 : 2 is :
[At \(45^\circ C\) vapour pressure of benzene is 280 mm Hg and that of octane is 420 mm Hg. Assume Ideal gas]
-
The molar conductivity of 0.007 M acetic acid is 20 S cm\(^2\) mol\(^{-1}\). What is the dissociation constant of acetic acid ? Choose the correct option.
\(\Lambda^\circ_{H^+} = 350\) S cm\(^2\) mol\(^{-1}\), \(\Lambda^\circ_{CH_3COO^-} = 50\) S cm\(^2\) mol\(^{-1}\)
-
The slope of Arrhenius Plot (\(\ln k\) v/s \(\frac{1}{T}\)) of first order reaction is \(-5\times10^3\) K. The value of \(E_a\) of the reaction is. Choose the correct option for your answer.
[Given R=8.314 J K\(^{-1}\)mol\(^{-1}\)]
-
Match List - I with List - II.
List - I : (a) benzene \(\xrightarrow[\text{Anhyd. }AlCl_3/CuCl]{CO,\ HCl}\) (b) \(R-CO-CH_3 + NaOX \rightarrow\) (c) \(R-CH_2-OH + R'COOH \xrightarrow{\text{Conc. }H_2SO_4}\) (d) \(R-CH_2COOH \xrightarrow[\text{(ii) }H_2O]{\text{(i) }X_2/\text{Red P}}\)
List - II : (i) Hell-Volhard-Zelinsky reaction (ii) Gattermann-Koch reaction (iii) Haloform reaction (iv) Esterification
Choose the correct answer from the options given below.
-
The intermediate compound 'X' in the following chemical reaction is :
toluene \(+ CrO_2Cl_2 \xrightarrow{CS_2} X \xrightarrow{H_3O^+}\) benzaldehyde
-
For irreversible expansion of an ideal gas under isothermal condition, the correct option is :
NEET UG 2020 question paper (official, booklet E1)
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Identify a molecule which does not exist.
-
Find out the solubility of Ni(OH)\(_2\) in 0.1 M NaOH. Given that the ionic product of Ni(OH)\(_2\) is \(2\times10^{-15}\).
-
Identify the correct statements from the following :
(a) CO\(_2\)(g) is used as refrigerant for ice-cream and frozen food.
(b) The structure of C\(_{60}\) contains twelve six carbon rings and twenty five carbon rings.
(c) ZSM-5, a type of zeolite, is used to convert alcohols into gasoline.
(d) CO is colorless and odourless gas.
-
Hydrolysis of sucrose is given by the following reaction.
Sucrose + H\(_2\)O \(\rightleftharpoons\) Glucose + Fructose
If the equilibrium constant (K\(_c\)) is \(2\times10^{13}\) at 300 K, the value of \(\Delta_rG^{\ominus}\) at the same temperature will be :
-
Identify compound X in the following sequence of reactions :
Toluene (C\(_6\)H\(_5\)CH\(_3\)) \(\xrightarrow{Cl_2/h\nu}\) X \(\xrightarrow[373\ K]{H_2O}\) Benzaldehyde (C\(_6\)H\(_5\)CHO)
-
Identify the incorrect match.
Name | IUPAC Official Name
(a) Unnilunium | (i) Mendelevium
(b) Unniltrium | (ii) Lawrencium
(c) Unnilhexium | (iii) Seaborgium
(d) Unununnium | (iv) Darmstadtium
-
An element has a body centered cubic (bcc) structure with a cell edge of 288 pm. The atomic radius is :
-
Which of the following set of molecules will have zero dipole moment ?
-
On electrolysis of dil.sulphuric acid using Platinum (Pt) electrode, the product obtained at anode will be :
-
Reaction between acetone and methylmagnesium chloride followed by hydrolysis will give :
-
Which of the following oxoacid of sulphur has \(-\)O\(-\)O\(-\) linkage ?
-
Which of the following amine will give the carbylamine test ?
-
The calculated spin only magnetic moment of Cr\(^{2+}\) ion is :
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The correct option for free expansion of an ideal gas under adiabatic condition is :
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The freezing point depression constant (K\(_f\)) of benzene is 5.12 K kg mol\(^{-1}\). The freezing point depression for the solution of molality 0.078 m containing a non-electrolyte solute in benzene is (rounded off upto two decimal places) :
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The number of Faradays(F) required to produce 20 g of calcium from molten CaCl\(_2\) (Atomic mass of Ca = 40 g mol\(^{-1}\)) is :
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Reaction between benzaldehyde and acetophenone in presence of dilute NaOH is known as :
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Paper chromatography is an example of :
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An increase in the concentration of the reactants of a reaction leads to change in :
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A mixture of N\(_2\) and Ar gases in a cylinder contains 7 g of N\(_2\) and 8 g of Ar. If the total pressure of the mixture of the gases in the cylinder is 27 bar, the partial pressure of N\(_2\) is :
[Use atomic masses (in g mol\(^{-1}\)) : N = 14, Ar = 40]
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Identify the correct statement from the following :
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A tertiary butyl carbocation is more stable than a secondary butyl carbocation because of which of the following ?
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Which of the following is a cationic detergent ?
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Elimination reaction of 2-Bromo-pentane to form pent-2-ene is :
(a) \(\beta\)-Elimination reaction
(b) Follows Zaitsev rule
(c) Dehydrohalogenation reaction
(d) Dehydration reaction
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The mixture which shows positive deviation from Raoult's law is :
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Which of the following is the correct order of increasing field strength of ligands to form coordination compounds ?
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Which of the following is a basic amino acid ?
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HCl was passed through a solution of CaCl\(_2\), MgCl\(_2\) and NaCl. Which of the following compound(s) crystallise(s) ?
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Which of the following is a natural polymer ?
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Which of the following is not correct about carbon monoxide ?
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Sucrose on hydrolysis gives :
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The following metal ion activates many enzymes, participates in the oxidation of glucose to produce ATP and with Na, is responsible for the transmission of nerve signals.
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Which one of the followings has maximum number of atoms ?
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The number of protons, neutrons and electrons in \(^{175}_{71}\)Lu, respectively, are :
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What is the change in oxidation number of carbon in the following reaction ?
CH\(_4\)(g) + 4Cl\(_2\)(g) \(\rightarrow\) CCl\(_4\)(l) + 4HCl(g)
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Identify the incorrect statement.
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For the reaction, 2Cl(g) \(\rightarrow\) Cl\(_2\)(g), the correct option is :
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Measuring Zeta potential is useful in determining which property of colloidal solution ?
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Urea reacts with water to form A which will decompose to form B. B when passed through Cu\(^{2+}\) (aq), deep blue colour solution C is formed. What is the formula of C from the following ?
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Match the following and identify the correct option.
(a) CO(g) + H\(_2\)(g) (i) Mg(HCO\(_3\))\(_2\) + Ca(HCO\(_3\))\(_2\)
(b) Temporary hardness of water (ii) An electron deficient hydride
(c) B\(_2\)H\(_6\) (iii) Synthesis gas
(d) H\(_2\)O\(_2\) (iv) Non-planar structure
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Match the following :
Oxide | Nature
(a) CO (i) Basic
(b) BaO (ii) Neutral
(c) Al\(_2\)O\(_3\) (iii) Acidic
(d) Cl\(_2\)O\(_7\) (iv) Amphoteric
Which of the following is correct option ?
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The rate constant for a first order reaction is \(4.606\times10^{-3}\) s\(^{-1}\). The time required to reduce 2.0 g of the reactant to 0.2 g is :
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An alkene on ozonolysis gives methanal as one of the product. Its structure is :
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Which of the following alkane cannot be made in good yield by Wurtz reaction ?
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Anisole on cleavage with HI gives :
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The number of sigma (\(\sigma\)) and pi (\(\pi\)) bonds in pent-2-en-4-yne is :
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The structure of intermediate A in the following reaction, is :
[Reaction: cumene (isopropylbenzene) \(\xrightarrow{O_2}\) A \(\xrightarrow[H_2O]{H^+}\) phenol + acetone]
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The correct structure of tribromooctaoxide is :
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4d, 5p, 5f and 6p orbitals are arranged in the order of decreasing energy. The correct option is :
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Which of the following reactions are disproportionation reaction ?
(a) \(2Cu^{+} \to Cu^{2+} + Cu^{0}\)
(b) \(3MnO_4^{2-} + 4H^{+} \to 2MnO_4^{-} + MnO_2 + 2H_2O\)
(c) \(2KMnO_4 \xrightarrow{\Delta} K_2MnO_4 + MnO_2 + O_2\)
(d) \(2MnO_4^{-} + 3Mn^{2+} + 2H_2O \to 5MnO_2 + 4H^{\oplus}\)
Select the correct option from the following :
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Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is :
[Given that 1 L bar = 100 J]
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Among the following, the one that is not a green house gas is :
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For the cell reaction
\(2Fe^{3+}(aq) + 2I^{-}(aq) \to 2Fe^{2+}(aq) + I_2(aq)\)
\(E^{\ominus}_{cell} = 0.24\) V at 298 K. The standard Gibbs energy (\(\Delta_rG^{\ominus}\)) of the cell reaction is :
[Given that Faraday constant F = 96500 C mol\(^{-1}\)]
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Enzymes that utilize ATP in phosphate transfer require an alkaline earth metal (M) as the cofactor. M is :
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The most suitable reagent for the following conversion, is :
\(H_3C-C\equiv C-CH_3 \to\) cis-2-butene
