The density of a monobasic strong acid (Molar mass 24.2 g mol) is 1.21 kg L. The volume of its solution required for the complete neutralization of 25 mL of 0.24 M NaOH is $$10^{-2}$$ mL (Nearest integer)

Find the volume of monobasic strong acid solution required to neutralize 25 mL of 0.24 M NaOH.

The molarity of the acid solution can be determined from its density and molar mass. With density = 1.21 kg/L = 1210 g/L and molar mass = 24.2 g/mol, the molarity is $$\frac{1210}{24.2} = 50$$ M.

For a monobasic strong acid neutralizing NaOH, the condition $$M_1V_1 = M_2V_2$$ applies. Substituting $$M_1 = 50$$ M, $$M_2 = 0.24$$ M and $$V_2 = 25$$ mL gives $$50 \times V_1 = 0.24 \times 25\,. $$

Solving for $$V_1$$ yields $$V_1 = \frac{0.24 \times 25}{50} = \frac{6}{50} = 0.12\text{ mL}$$ and expressing this in the required form gives $$V_1 = 0.12\text{ mL} = 12 \times 10^{-2}\text{ mL}\,,$$ so the required volume is $$\boxed{12}$$.