Chapter 9, Problem 79A

Interpretation Introduction

Interpretation: Whether the given sample is nitrous oxide or not is to be explained.

Concept Introduction : According to the law of multiple proportions, the two elements form more compounds, than the ratios of the second element’s masses, which combined with the fixed first’s element mass will always be ratios of small whole numbers.

Answer to Problem 79A

The ratio of nitrogen to oxygen is 42:26 which is not equal to 7:4. So, the given sample is not nitrous oxide.

Explanation of Solution

It is given that the mass ratio of nitrogen to oxygen is 7:4. It means that 7 g of N will combine with 4 g of oxygen to form nitrous oxide.

The 68 g of the sample contains 42 g of nitrogen. The amount of oxygen is $68-42=\text{26}\text{g}$. The ratio for the given grams is calculated as follows:

  $\frac{\text{Mass}\text{of}\text{N}}{\text{Mass}\text{of}\text{O}}=\frac{42\text{g}}{26\text{g}}\ne 7:4$

Therefore, the ratio of nitrogen to oxygen is 42:26 which is not equal to 7:4. So, the given sample is not nitrous oxide.