Question

pH of a 0.1 M monobasic acid is found to be 2. Hence, its osmotic pressure at a given temperature T K is

• A. 1.1 RT
• B. 0.1 RT
• C. 0.11 RT
• D. 0.01RT

Answer 1

Answer: (C)

$p$H = 2
$\therefore$ $[H^{+}]=10^{-2}$
$C\alpha =10^{-2}\alpha =\frac{10^{-2}}{10^{-1}}=10^{-1}$
$i=1+\alpha$
$i=1+0.1=1.1$
$\pi V=inRT\pi =i\left(\frac{n}{V}\right)RT$
= $1.1\times 0.1\times RT$ = 0.11 RT.