Final answer:
The differing mass ratios of carbon to hydrogen in compounds X and Y support the law of multiple proportions, demonstrating that they are different compounds.
Step-by-step explanation:
A sample of compound X and a sample of compound Y both contain carbon and hydrogen in specific amounts that characterize each compound. When comparing the mass ratios, X has a ratio of carbon to hydrogen of 14.13 g C to 2.96 g H, while Y has a ratio of 19.91 g C to 3.34 g H. These differing mass ratios of the same elements in different compounds exemplify the law of multiple proportions, indicating that X and Y are indeed different compounds.
According to the law of multiple proportions, if two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in ratios of small whole numbers. For instance, the ratios of carbon to hydrogen in X and Y are different, thus supporting the law. This principle helps in studying and understanding the composition of chemical compounds and the fundamental relationships between different compounds.