NTSE Stage 2 SAT 2014 Question Paper

        Proton  Neutron
∵ Element A → 13    + 14   = 27
∴ Element B → 8    +  8   = 16
∴ $\mathrm{A}{=}_{13}\mathrm{A}{\mathrm{I}}^{27},\mathrm{B}{=}_8{\mathrm{O}}^{16}$
Formula of compound of elements A and B is $\mathrm{A}{=}_{13}\mathrm{A}{\mathrm{I}}^{27},\mathrm{B}{=}_8{\mathrm{O}}^{16}$
Hence, formula unit mass
$=\left(22\times 2\right)+\left(16\times 3\right)$
$=55+48=102$