$2g$ NaCl $150m$

$\%.$ mass$/$volume concentration

$2$gNaC$\frac{l}{150}mL100=1\mathrm{.}33$

Molarity

$Na$:$22\mathrm{.}99=58\mathrm{.}443$

$Cl$: $35\mathrm{.}453$

$\frac{2g1(mol)}{58\mathrm{.}443},258\mathrm{.}443$

$0\mathrm{.}0342$molNa$\frac{d}{.}15L$

$0\mathrm{.}034215L=0\mathrm{.}228m$

osmolarity

$2$ osmules

$0\mathrm{.}342\mathrm{.}152=0\mathrm{.}456$

Is this correct