If 20 " mL of " 0.1 M `K_(2)Cr_(2)O_(7)` is required to titrate 10 " mL of " a liquid iron supplement, then the concentration of iron in the the the vitamin solution is

Options

A. 1.2 M
B. 2.4 M
C. 0.6 N
D. 1.56 M

Answer

A

Explanation

`Cr_(2)O_(7)^(2-)+Fe^(2+)to2Cr^(3+)+Fe^(3+)`
(i). `6e^(-)+Cr_(2)O_(7)^(2-)to2Cr^(3+)(x=6)`
`(ii). `Fe^(2+)toFe^(3+)+e^(-)(x=1)`
`m" Eq of "Cr_(2)O_(7)^(2-)=m" Eq of "Fe^(2+)`
`20xx0.1xx6m" Eq of "10xxN`
`N=1.2`
`M=(N)/("n-factor")=(1.2)/(1)=1.2M`