Chapter 10.5, Problem 79SSC

Interpretation Introduction

Interpretation:

The generalized formula of hydrate needs to be determined.

Concept introduction:

The relation between number of moles, mass and molar mass of a substance is represented as follows:

$n=\frac{m}{M}$

Here, m is mass and M is molar mass.

Answer to Problem 79SSC

$A_x{B}_y.5{\text{ H}}_{\text{2}}\text{O}$

Explanation of Solution

Given information:

Moles of water $=0.050\text{ mol}\text{.}$

Moles of ionic compound $=0.00998\text{ mol}\text{.}$

The ratio of number of moles of water and ionic compound can be calculated as follows:

Dividing the moles by lowest moles,

$\begin{array}{l}\text{Moles of water = }\frac{0.050}{0.00998}=5.10\approx 5\\ \text{Moles of ionic compound}=\frac{0.00998}{0.00998}=1\end{array}$

Therefore, the general formula of hydrated ionic compound is $A_x{B}_y.5{\text{ H}}_{\text{2}}\text{O}$

Conclusion

Thus, the general formula of hydrated ionic compound is $A_x{B}_y.5{\text{ H}}_{\text{2}}\text{O}$