Question

The total molarity and normality of all the ions present in $1$ litre solution containing $0.1$ M of $CuS{O}_4$ and $0.1$ M of ${Al}_2{\left(S{O}_4\right)}_3$ is :

• A. 0.2 M ,0.4 N
• B. 0.7 M, 1.6 N
• C. 0.8 M, 1.6 N
• D. 0.105 M, 2.10 N

Answer 1

The correct option is B 0.7 M, 1.6 N

Total no of moles of ions in solution is $0.1$ M of $CuS{O}_4$ which gives mole of ${Cu}^{2+}=0.1$ mole of $S{O}_4^{2-}=0.1$ mole

Also, $0.1$ M of $A{l}_2(S{O}_4{)}_3$ gives $0.2$ mole of ${Al}^{3+}$ and $0.3$ mole of $S{O}_4^{2-}$.

$\therefore$ Total no of moles of ions present in 1 litre of solution $=0.1+0.1+0.2+0.3=0.7M$

$0.1$ M of $CuS{O}_4$ gives $0.2$ eq.of ${Cu}^{2+}$ and $0.2$ eq.of $S{O}_4^{2-}$.

Also, $0.1$ M of $A{l}_2(S{O}_4{)}_3$ gives $0.6$ eq. of ${Al}^{3+}$ and $0.6$ eq.of $S{O}_4^{2-}$.

$\therefore$ Total eq. = $0.2+0.2+0.6+0.6=1.6N$

Hence, option B is correct.