Question

Consider a titration of potassium dichromate solution with acidified Mohr's salt solution using diphenylamine as indicator. the number of moles of Mohr's salt required per mole of dichromate is

• A. 3
• B. 4
• C. 5
• D. 6

Answer 1

The correct option is D 6

n - factor of dichromate is 6.
Also, n - factor of Mohr's salt is 1 as:
$FeS{O}_4(N{H}_4{)}_{2}S{O}_4.6H_{2}O\stackrel{O.A}{\to }F{e}^{3+}$
$\because$ 1 mole of dichromate = 6 equivalent of dichromate.
$\therefore$ 6 equivalent of Mohr's salt would be required.
Since, n - factor of Mohr's salt is 1, 6 equivalent of it would also be equal to 6 moles.