Question

The electrolyte in lead storage battery is dilute sulpguric acid. The concentration of sulphuric acid in a lead-storage battery must be between $4.8M$ and $5.3M$ for most efficient functioning. A $5mL$ sulphuric acid sample of a particular battery requires $50mL$ of $1.0M$ $NaOH$ for complete neutralisation. Which of the following statements about the functioning of battery is the most appropriate?

• A. The acid concentration in the battery is not in the most effective range
• B. The add concentration in the battery is in the most effective range
• C. The add concentration in the battery is hardly in the most effective range
• D. Only a good mechanic can tell whether or not the add concentration in the battery is in the most effective range

Answer 1

Answer: (B)

Volume of sample of sulphuric acid $=5mL$ Volume of $NaOH$ required for neutralisation $=50mL$

Normality of $NaOH$ required for neutralisation

$=1.0M=1.0N$

Normality of sample of sulphuric acid $=?$

$\because N_1{V}_1=N_2{V}_2$

$N_1=\frac{1.0\times 50}{5}=10N$

$\therefore$ Molarity = $\frac{\text{ normality }}{\text{ valence }}=\frac{10}{2}=5M$

Thus, the acid concentration in lead storage battery is in the most effective range (ie, between $4.8$ and $5.3M$ ).