Question

The dichromate ion oxidises stannous ions in solution according to the reaction:

$3S{n}^{2+}+14H^{+}+C{r}_2{O}_7^{2-}\to 3S{n}^{4+}+2C{r}^{3+}+7H_{2}O$.

How many ml of $K_{2}C{r}_2{O}_7$ solution of 0.5 M strength will be required to completely react with 0.5 moles of tin(II) chloride in solution?

• A. $666.6ml$
• B. $444.4ml$
• C. $222.2ml$
• D. $333.3ml$

Answer 1

The correct option is D $333.3ml$

In the above question, we need to apply the Normality equation as follows:

$N_1{V}_1=N_2{V}_2$

$(M_1\times V.F.)V_1=(M_2\times V.F.)V_2$

$0.5\times 6\times V_1=0.5\times 2\times 1000$

Therefore, $V_1=\frac{1000}{3}$

$V_1=333.3ml$

Thus option D is correct.