Every question from past board papers on d- and f-Block Elements, newest paper first. Open any question for its full worked answer.
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 :
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 :
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
'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:
The pair of lanthanoid ions which are diamagnetic is
The stability of Cu\(^{2+}\) is more than Cu\(^+\) salts in aqueous solution due to -
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 :
The reaction that does NOT take place in a blast furnace between 900 K to 1500 K temperature range during extraction of iron is :
Gadolinium has a low value of third ionisation enthalpy because of
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
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 :
Which one of the following methods can be used to obtain highly pure metal which is liquid at room temperature ?
The maximum temperature that can be achieved in blast furnace is :
Zr (Z=40) and Hf (Z=72) have similar atomic and ionic radii because of :
The incorrect statement among the following is :
The calculated spin only magnetic moment of Cr\(^{2+}\) ion is :
Identify the correct statement from the following :
Identify the incorrect statement.
The manganate and permanganate ions are tetrahedral, due to :
Which one is malachite from the following ?
The reason for greater range of oxidation states in actinoids is attributed to :
Extraction of gold and silver involves leaching with \(CN^-\) ion. Silver is later recovered by :
Match items of Column I with the items of Column II and assign the correct code :
Column I: (a) Cyanide process; (b) Froth floatation process; (c) Electrolytic reduction; (d) Zone refining
Column II: (i) Ultrapure Ge; (ii) Dressing of ZnS; (iii) Extraction of Al; (iv) Extraction of Au; (v) Purification of Ni
Code: (a) (b) (c) (d)
Which one of the following statements is correct when \(SO_2\) is passed through acidified \(K_2Cr_2O_7\) solution ?
The electronic configurations of Eu (Atomic No. 63), Gd (Atomic No. 64) and Tb (Atomic No. 65) are :
Which one of the following statements related to lanthanons is incorrect?
