Question

The density of a monobasic strong acid (Molar mass $242 \,g$ mol) is $121 \,kg \,L$ The volume of its solution required for the complete neutralization of $25 \,mL$ of $024\, M\, NaOH$ is ___$\times 10^{-2} mL$ (Nearest integer)

Answer 1

Correct Answer: 12

The correct answer is 12
millimole of $NaOH=0.24\times 25$
$\therefore$ millimole of acid $=0.24\times 25$
$\Rightarrow$ mass of acid $=0.24\times 25\times 24.2mg$
for pure acid,
$V=\frac{w}{d};(d=1.21kg/L=1.21g/ml)$
$\therefore V=\frac{0.24\times 25\times 24.2}{1.12}\times 10^{-3}$
$=120\times 10^{-3}ml$
$=12\times 10^{-2}ml$