Daily Practice Problems
Class 12 Chemistry
The d and f block elements
daily practice problem


How will you compare the ionic radii of same element in different oxidation state?


Give three uses of K2Cr2O7.


Manganate and Permanganate ion have –

(i) sp2 Hybridization and trigonal planer shape

(ii) sp Hybridization and Linear in shape

(iii) sp3 and tetrahedral shape

(iv)sp2d2 and trigonal bipyramidal in shape


What is Baeyer’s reagent? What happen if Baeyer’s reagent reacts with ethylene?


Complete the following reactions –

(i) chromate ion + Sodium carbonate à

(ii) I- + MnO-4 + H+ à

(iii) What if copper oxide is heat with CuS?


Name element whose ion do not have f0, f7 or f14  Configuration also posses +2 and +4 oxidation state.

(i) Neodymnium

(ii) Lutetium

(iii) Holmium

(iv) None of these


What is the use of Actinides?


The magnetic moment is associated with its spin angular momentum and orbital angular momentum. Spin only magnetic moment value of Cr3+ and Co2+ion is –

(a) 3.87 BM and 2.78BM

(b) 1.9 BM and 2.3 BM

(c) 3.87 BM and 3.87 BM

(d) 4.2 BM and 3.87 BM


The correct order of decreasing second ionisation Enthalpy of Ti, V Cr and Mn

(a) Mn > Cr >Ti > V

(b) Ti >V >Cr > Mn

(c) Cr > Mn > V > Ti

(d) V > Mn >Cr >Ti


In context with the transition element, which of the following statement is incorrect?

(a) In addition to the normal oxidation states, the zero oxidation state is also shown by these elements in complexes.

(b) In the highest oxidation states, the transition metal shows basic character and form anionic complexes.

(c) In the highest oxidation states of the first five transition elements (Sc to Mn), all the 4s and 3d electrons are used for bonding.

(d) Once the d5 configuration is exceeded, the tendency to involve all the 3d electrons in bonding decreases.


Which of the following factor may be regarded as the main cause of lanthanide contraction?

(a) Poor shielding of one of 4f electron by another in the subshell.

(b) Effective shielding of one of 4f electrons by another in the subshell.

(c) Poorer shielding of 5d electrons by 4f electrons.

(d) Greater shielding of 5d electrons by 4f electrons.


What is Mischmetall? What are its uses?


Name an element among the first series of transition metal from Sc (Z = 21) to Zn (Z = 30) which shows only (+3) oxidation state.


How the standard reduction potential of tansition metals can be used to compare their stability in aqueous medium in a particular inoic state?


What happen if K2Cr2O7 reacts with H2O2?

(i) In acidic medium (ii) in less acidic medium (iii) in alkaline medium


Write down the following reaction.

(a) Disproportionation of Mn3+ in acidic medium.

(b) Disproportionation of MnO42- in alkaline medium.

(c) Disproportionation of MnO42- in acidic medium.


The ‘spin only’ magnetic moment of Ni2+ in aqueous solution would be : [At.No.Ni = 28]

(a) 0

(b) 5

(c) 3.1

(d) 2.84


Why Cd2+ salts are white?


A reduction in the atomic size with increase in atomic number is a characteristics of the

elements having __________.

(a) high atomic masses

(b) radioactive series

(c) d-block

(d) f- block


Match the Catalysts given in column I with the process given in column II.

                        Column I


                    Column II


  1. Ni in the presence of hydrogen

Zieglar Natta catalyst

  1. Cu2Cl2

Contact process

  1. V2O5

Vegetable oil to ghee

  1. Finely divided iron

Sandmeyer reaction

  1. TiCl4 + Al(CH3)3

Haber’s Process


Decomposition of KClO3