Question

Among the following, solution which shows the lowest osmotic pressure is -

• A. 0.20 m KCl
• B. $0.05mCaC{l}_2$
• C. $0.08m{K}_3\left[Fe\right(CN{)}_6]$
• D. $0.04mFeC{l}_3$

Answer 1

The correct option is B $0.05mCaC{l}_2$

$\pi =C_{effective}^{RT}\left(a\right)C_{effective}=0.2\times 2=0.4m\left(b\right)C_{effective}=0.05\times 3=0.15m\left(c\right)C_{effective}=0.08\times 4=0.32\left(d\right)C_{effective}=0.04\times 4=0.16m$
$C_{effective}$ is lowest for (b)