Question

A current of 3.7 A is passed for 6 hrs between Pt electrodes in 0.5 L of 2M solution of $Ni(N{O}_3{)}_2$. What will be the molarity of solution at the end of electrolysis ?

• A. $1.172$ M
• B. $1.643$ M
• C. $2.145$M
• D. None of these

Answer 1

The correct option is A $1.172$ M

As we know,

Molar mass of $Ni(N{O}_3{)}_2=182g/mol$

Again,

$W=Zit=\frac{Eit}{96500}=\frac{91\times 3.7\times 6\times 60\times 60}{96500}=75.37gm$

So, remaining amount of nickel nitrate in solution is 182-75.37 = 106.63 gm

molarity of solution at the end is $\frac{\mathrm{106..63}}{0.5\times 182}=1.172M$