During the discharge of a lead storage battery, the density of sulphuric acid fell from 1.294 to 1.139 g mL−1. Sulphuric acid of density 1.294 g mL−1 is 39 % H2SO4 by mass and that of density 1.139 g mL−1 is 20 % H2SO4 by mass. The battery holds 3.5 L of the acid and the volume remained practically constant during the discharge. The charging and discharging reactions arePb+SO2−4→PbSO4+2e− (charging)PbO2+4H++SO2−4+2e−→PbSO4+2H2O (discharging)The number of ampere-hour for which the battery must have been used is

During the discharge of a lead storage battery, the density of sulphur

1.	During the discharge of a lead storage battery, the density of sulphuric acid fell from 1.294 to 1.139 g mL−1. Sulphuric acid of density 1.294 g mL−1 is 39 % H2SO4 by mass and that of density 1.139 g mL−1 is 20 % H2SO4 by mass. The battery holds 3.5 L of the acid and the volume remained practically constant during the discharge. The charging and discharging reactions arePb+SO2−4→PbSO4+2e− (charging)PbO2+4H++SO2−4+2e−→PbSO4+2H2O (discharging)The number of ampere-hour for which the battery must have been used is
Answer» During the discharge of a lead storage battery, the density of sulphuric acid fell from $1.294$ to $1.139 {g mL}^{- 1}$ . Sulphuric acid of density $1.294 {g mL}^{- 1}$ is $39 % H_{2} S O_{4}$ by mass and that of density $1.139 {g mL}^{- 1}$ is $20 % H_{2} S O_{4}$ by mass. The battery holds $3.5 L$ of the acid and the volume remained practically constant during the discharge. The charging and discharging reactions are $P b + S O_{4}^{2 -} \to P b S O_{4} + 2 e^{-}$ (charging) $P b O_{2} + 4 H^{+} + S O_{4}^{2 -} + 2 e^{-} \to P b S O_{4} + 2 H_{2} O$ (discharging) The number of ampere-hour for which the battery must have been used is