Chapter 9, Problem 102A

Interpretation Introduction

Interpretation: The other law showed or obeyed by white compound is to be stated.

Concept Introduction : Law of definite proportions is also known as law of constant proportion. It stated that a compound always contains a constant and fixed ratio of its constituent elements.

Answer to Problem 102A

The mass of products is equal to the mass of reactant. Thus, white compound shows the law of conversation of mass.

Explanation of Solution

It is given that student heated 5.00 g of a white compound and obtained 3.60 g of a green compound and 1.40 g of colorless gas. Another student heated a 9.00 g sample of the same compound and obtained 6.48 g of a green compound and 2.52 g of colorless gas.

The ratio for the compounds is calculated as follows:

  $\begin{array}{c}\text{White}\text{compound}=\frac{5.00}{9.00}\\ =0.56:1\\ \text{Green}\text{compound}=\frac{3.60}{6.48}\\ =0.56:1\end{array}$

  $\begin{array}{c}\text{Colorless}\text{gas}=\frac{1.40}{2.52}\\ =0.56:1\end{array}$

The ratios are same for the both the compounds. Thus, the white compound shows the law of definite proportions.

The general reaction is given as follows:

  $\text{White}\text{compound}\stackrel{\text{Heated}}{\to }\text{Green}\text{compound}+\text{Colorless}\text{gas}$

The mass of products is calculated as follows:

  $\begin{array}{c}\text{Mass}\text{of}\text{products}=\text{Green}\text{compound}+\text{Colorless}\text{gas}\\ =3.60\text{g}+1.40\text{g}\\ =\text{5}\text{.00}\text{g}\end{array}$

So, it is equal to the mass of reactant. Thus, white compound shows the law of conversation of mass.