#neet
- Use of bioresources by multinational companies and organisations without authorisation from the concerned country and its people is called Answer: 3. Biopiracy Using biological resources or related knowledge without proper authorisation and payment is called biopiracy. Biodegrad... 1
- A ‘new’ variety of rice was patented by a foreign company, though such varieties have been present in India for a long time. This is related to Answer: 4. Basmati A foreign company patented Basmati rice (a US patent to RiceTec), though India has grown basmati for centuries. Co-667 is... 1
- Select the *correct* match : Answer: 1. Ribozyme – Nucleic acid A ribozyme is an RNA molecule with catalytic activity, so it is a nucleic acid. Morgan is linked to linka... 1
- Niche is Answer: 4. the functional role played by the organism where it lives Niche is the functional role of an organism in its habitat, including i... 1
- In stratosphere, which of the following elements acts as a catalyst in degradation of ozone and release of molecular oxygen ? Answer: 3. Cl UV rays split chlorofluorocarbons and release chlorine atoms, which act as catalysts in converting ozone to molecular oxygen.... 1
- What type of ecological pyramid would be obtained with the following data ?Secondary consumer : 120 gPrimary consumer : 60 gPrimary producer : 10 g Answer: 1. Inverted pyramid of biomass A pyramid of biomass is inverted when higher trophic levels have more biomass than lower ones. Here b... 1
- The Golgi complex participates in Answer: 3. Formation of secretory vesicles The Golgi complex packs and sorts proteins and lipids into vesicles, including secretory vesicles... 1
- Which of the following is true for nucleolus ? Answer: 4. It is a site for active ribosomal RNA synthesis. The nucleolus is a non-membranous site of active rRNA synthesis and ribosome ass... 1
- Iron carbonyl, Fe(CO)_5 is Answer: 3. mononuclear Fe(CO)₅ contains one metal atom, so it is mononuclear. Dinuclear and polynuclear carbonyls like mathrmMn₂(CO)₁₀ and m... 1
- Pneumatophores occur in Answer: 1. Halophytes Pneumatophores are breathing roots that grow upward out of waterlogged, salty soil. They are found in mangrove plants... 1
- Which of the following carbocations is expected to be most stable ? Answer: 2. cyclohexadienyl cation with NO ₂ at top carbon, H and Y on the sp ³ carbon, positive charge adjacent (picture) In the intermediat... 1
- Which of the following is correct with respect to -I effect of the substituents ? (R = alkyl) Answer: 3. - NR ₂ < - OR < - F The -I effect increases with the electronegativity of the atom attached to the carbon chain: N < O < F. Since... 1
- The type of isomerism shown by the complex [CoCl_2(en)_2] is Answer: 1. Geometrical isomerism [CoCl₂(en)₂] is octahedral of type [M(AA)₂X₂] . The two Cl can be adjacent (cis) or opposite (trans), so it... 1
- Which one of the following ions exhibits d-d transition and paramagnetism as well ? Answer: 4. MnO ₄²⁻ d-d transitions need partly filled d orbitals; paramagnetism needs unpaired electrons. mathrmCrO₄²⁻ : Cr(+6), d⁰ . MnO₄^-... 1
- Match the metal ions given in Column I with the spin magnetic moments of the ions given in Column II and assign the correct code :Column I: a. Co^3+; b. Cr^3+; c. Fe^3+; d. Ni^2+Column II: i. √(8) B.M.; ii. √(35) B.M.; iii. √(3) B.M.; iv. √(24) B.M.;… Answer: 1. a-iv, b-v, c-ii, d-i Use μ=√(n(n+2)) with n unpaired electrons. mathrmCo³⁺ ( d⁶ , high spin, n = 4): √(24) (iv). mathrmCr³⁺ ( d³... 1
- The geometry and magnetic behaviour of the complex [Ni(CO)_4] are Answer: 3. tetrahedral geometry and diamagnetic In [Ni(CO)₄] Ni is in the zero oxidation state with configuration 3d⁸ 4s² . CO is a strong-f... 1
- The correct difference between first- and second-order reactions is that Answer: 3. the half-life of a first-order reaction does not depend on [A] ₀ ; the half-life of a second-order reaction does depend on [A] ₀... 1
- Among CaH_2, BeH_2, BaH_2, the order of ionic character is Answer: 1. BeH ₂ < CaH ₂ < BaH ₂ Ionic character of a metal hydride increases with the electropositive (metallic) character of the metal, wh... 1
- In which case is the number of molecules of water maximum ? Answer: 1. 18 mL of water Compare the number of moles; more moles means more molecules. 18 mL water = 18 g (density 1 g/mL) = 1 mol. 0.00224... 1
- Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below :BrO_4^- 1.82\ V BrO_3^- 1.5\ V HBrO 1.595\ V Br_2 1.0652\ V Br^-Then the species undergoing disproportionation is Answer: 4. HBrO A species disproportionates if the emf for its reduction (to the species on one side) is higher than the emf for its oxidati... 1
- The bond dissociation energies of X_2, Y_2 and XY are in the ratio of 1 : 0.5 : 1. ΔH for the formation of XY is -200 kJ mol^-1. The bond dissociation energy of X_2 will be Answer: 2. 800 kJ mol ⁻¹ Let the bond energies be X-X = a , Y-Y = 0.5a , X-Y = a . For 1/2X₂+1/2Y₂→XY : Δ H=1/2 a+1/2(0.5a)-a=-0.25a . -0.25... 1
- When initial concentration of the reactant is doubled, the half-life period of a zero order reaction Answer: 3. is doubled For a zero-order reaction, t_(1/2)=[A]₀/2k , directly proportional to the initial concentration. If [A]₀ is doubled, t... 1
- For the redox reactionMnO_4^- + C_2O_4^2- + H^+ Mn^2+ + CO_2 + H_2Othe correct coefficients of the reactants for the balanced equation are(columns: MnO_4^-, C_2O_4^2-, H^+) Answer: 3. 2, 5, 16 Balance by the ion-electron method. Reduction: mathrmMnO₄^-+8H^++5e^-→ Mn²⁺+4H₂O . Oxidation: mathrmC₂O₄²⁻→2CO₂+2e^- . M... 1
- Which one of the following conditions will favour maximum formation of the product in the reaction,A_2(g) + B_2(g) ⇌ X_2(g) Δ_rH = -X kJ ? Answer: 1. Low temperature and high pressure Apply Le Chatelier's principle to A₂+B₂⇌ X₂ , which is exothermic and reduces the number of gas... 1