Barium chloride crystals contains 14.8 water fo crystallisation. Find the number of molecules fo water of crystallisation per molecule.

$BaC{l}_2.n{H}_{2}O$
Ba has mass of 137 g
Cl atomic mass = 35.5 g
Molecular mass of $H_{2}O$ = 18
14.8% water means
14.8 g water in 100 g of $BaC{l}_2.n{H}_{2}O$
n$\times$18 g water in [137+71+18n]
$\frac{n\times 18}{137+71+18n}$ = 14.8
on solving,
n = 2.0073 i.e n= 2
2 molecule of water of crystallisation are present in 1 molecule.