Which of the following options does not represent concentration of semi-molal aqueous solution of $\mathrm{NaOH}$ having $d_{\text{solution }}=1.02\mathrm{g}/\mathrm{ml}?$

Semi molal $\Rightarrow \frac{1}{2}\mathrm{m}$

$d=1.02\mathrm{g}/\mathrm{mL}$

1 kg of water contains $\frac{1}{2}$ mole of $\mathrm{NaOH} (20 \mathrm{gm})$

Mass of solution $=1000+20=1020 \mathrm{gm}$

Volume of solution $=\frac{1020}{1.02}=1000\mathrm{ml}=1\mathrm{L}$

$\begin{array}{l}M=\frac{\frac{1}{2}}{1}=\frac{1}{2}\\ X_{\mathrm{NaOH}}=\frac{\frac{1}{2}}{\frac{1}{2}+\frac{1000}{18}}=\frac{9}{1009}\end{array}$

$\mathrm{\%}\mathrm{w}/\mathrm{w}=\frac{20}{1020}\times 100\mathrm{\%}\mathrm{w}/\mathrm{v}=\frac{20}{1000}\times 100=2\mathrm{\%}$