Question

What volume (in ml) of 0.25 N solution of HCl is required to neutralize 5 grams of crystalline NaOH which is dissolved in water?

• A. 150 ml
  
• B. 250 ml
• C. 500 ml
• D. 750 ml
• E. 3750 ml

Answer 1

Answer: (C)

500 ml

First, calculate the number of moles of $NaOH$ present in 5 grams. The molar mass of $NaOH$ is 40 g/mol.
Number of moles of $NaOH$ in 5 gram $=\frac{5}{40}=0.125$ moles.

The moles of $HCl$ needed $=$ moles of $NaOH$

$M_1{V}_1=M_2{V}_2$

$0.25\times V_1=0.125\times 1000$

$V_1=\frac{0.125\times 1000}{0.25}=500$ mL

Option C is correct.