How many number of faradays of
electricity are required for three
liters of 0.5 M `K_(2)Cr_(2)O_(7)`
Solution to completely reduced in the acidic medium ?

Answer

9

Explanation

`K_(2)Cr_(2)O_(7) overset("acidic medium")rarr Cr^(3+)`
n factor = 6
charge on a mole `e^(o)=1F`
1 mole `K_(2) Cr_(2)O_(7)` gives 6F
charge of electricity required.
Total mole of
`K_(2)Cr_(2)O_(7)=M xx V=0.5 xx 3=1.5`
Requires electricity in faradays
`=1.5 xx 6=9F`