3.114_CP - Chemistry: Molecular Nature Of Matter And Change

Question

Narceine is a narcotic in opium that crystallizes from solution as a hydrate that contains 10.8 mass % water and has a molar mass of 499.52 g/mol. Determine x in narceine.xH₂O.

Step-by-Step Solution

Answer

The value of x in narceine is 3 moles of water molecules.

Finding the mass of water

There are 499.52 grams of narceine in 1 mole. On multiplying the narceine mass in 1 mole.

$\begin{array}{l}\mathrm{Mass}\mathrm{of}{\mathrm{H}}_2\mathrm{O}=0.108\times (499.52\mathrm{g})\\ =53.9\mathrm{g}{\mathrm{H}}_2\mathrm{O}\end{array}$

Finding the value of x in narceine

On multiplying the molar mass of water reciprocal which 18.02 g/mol to find x.

$\begin{array}{l}\mathrm{x}=53.9\mathrm{g}{\mathrm{H}}_2\mathrm{O}\times \frac{1\mathrm{mol}{\mathrm{H}}_2\mathrm{O}\mathrm{molecules}}{18.02\mathrm{g}{\mathrm{H}}_2\mathrm{O}}\\ \mathrm{x}=3\mathrm{mol}{\mathrm{H}}_2\mathrm{O}\mathrm{molecules}\end{array}$