Question

How many moles of mercury will be produced by electrolysing 1.0 M `Hg(NO_(3))_(2)` solution by a current of 2.0 A when passed for 3 hours ?

Answer 1

Quantity of charge passed (Q) `= Ixxt=(2.0 A)xx(3xx60xx60 s)`
`=(2.0 Axx10800 s)`=21600 AS=21600 C
`Hg(NO_(3))_(2)overset((aq))rarrHg^(2+)(aq)+2 NO_(3)^(-)(aq)`
`{:(Hg^(+)(aq)+2e^(-)rarrHg(s)),(" "2xx96500 C" "1 mol):}`
When `2xx96500` C is passed, mercury deposited =1 mol
When 21600 C is passed, mercury deposited `=(1 mol)xx((21600 C))/((2xx96500 C))=0.112 mol`