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:

Options

A. 3
B. 4
C. 5
D. 6

Answer

D

Explanation

The following redox change takes place:
`6e^(-)+Cr_(2)O_(7)^(2-)to2Cr^(3+)(n=6)`
`Fe^(2+)toFe^(3+)(n=1)` (from Mohr's salt)
`1 Eq-=1Eq`
`(1)/(6)mol=(1)/(1)mol`
`1 mol=6 mol` of Mohr's salt