In the standardization of $N{a}_2{S}_2{O}_3 u\sin g K_{2}C{r}_2{O}_7$ by iodometry, the equivalent weight of $K_{2}C{r}_2{O}_7$ is:

(1) (Molecular weight)/2

(2) (Molecular weight)/6

(3) (Molecular weight)/3

(4) same as molecular weight

The number of moles of Mohr's salt required per mole of dichromate ion is:

(1) 3

(2) 4

(3) 5

(4) 6

Which of the following pairs of substances on reaction will not evolve gas?

1. Iron, and ${\mathrm{H}}_2{\mathrm{SO}}_4$ (aq)

2. Iron, and steam

3. Copper, and HCl(g)

4. Sodium, and ethyl alcohol

When $KMn{O}_4$ acts as an oxidising agent and ultimately forms $Mn{O}_4^{2-}, Mn{O}_2, M{n}_2{O}_3 and M{n}^{2+}$, then the number of electrons transferred in each case respectively is:

1. 4,3,1,5

2. 1,5,3,7

3. 1,3,4,5

4. 3,5,7,1

Which one of the compounds does not decolorized an acidified solution of $KMn{O}_4$?

1. $S{O}_2$

2. $FeC{l}_3$

3. $H_2{O}_2$

4. $FeS{O}_4$

Which of the following has the highest negative $\left(\raisebox{1ex}{${\mathrm{M}}^{2+}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{M}$}\right.\right)$ standard electrode potential ?

1. Ti

2. Cu

3. Mn

4. Zn

The magnetic moment of an Mn²⁺ ion is equal to:

Incorrect statement among the following is  : 

1. La(OH)₃ is less basic than Lu(OH)₃

2. In lanthanoid series ionic radius of Ln³⁺ ions decreases.

3. La is actually an element of transition metal series rather than lanthanide series.

4. Atomic radii of Zr and Hf are same because of lanthanide contraction.

When the sample of copper with zinc impurity is to be purified by electrolysis,

the appropriate electrodes are 
 

Cathode                          Anode 

(1) pure zine                     pure copper       

(2) pure copper                 impure sample 

(3) impure zinc                  impure sample 

(4) impure sample             pure copper 

What is produced when excessive diluted nitric acid is combined with potassium chromate?

1. Cr₂O₇^2- and H₂O  

2. Cr³⁺ and Cr₂O₇^2-  

3. CrO₄^2-  

4. Cr₂O₄^2-