A lead storage battery has been used for one month (30 days) at the rate of one hour per day by drawing a constant current of 2 amperes. H₂SO₄ consumed by the battery is 

The reactions occurring during discharge are:

Anode: Pb(s)+SO₄²⁻_(aq)→PbSO_4(s)+2e⁻

At cathode:PbO_2(s)  +  4H⁺(aq)+SO₄²⁻_(aq)+  2e⁻   = PbSO_4(s)+2H₂O_(l)

Overall reaction reaction: Pb_(s)+PbO_2(s)+2H₂SO₄    = 2PbSO_4(s)+2H₂O_(l)

Quantity of electricity consumed Q= i .t

The battery is working one hour per day for 30 days ;

total number of hours = 30 hours 

Q = (2A) (30×3600s) = 216000 C

 2 × 96500 coulombs consume H₂SO₄ = 2 moles

∴ 216000 coulombs will consume H₂SO₄ = $\frac{1}{96500}\times 216000=2.24 \mathrm{moles}$