Ethane and acetylene are two gaseous hydrocarbons. Chemical...

Ethane and acetylene are two gaseous hydrocarbons. Chemical analyses show that in one sample of ethane, $2.65 \mathrm{g}$ of carbon are combined with $0.665 \mathrm{g}$ of hydrogen, and in one sample of acetylene, $4.56 \mathrm{g}$ of carbon are combined with $0.383 \mathrm{g}$ of hydrogen. (a) Are these results consistent with the law of multiple proportions? (b) Write reasonable molecular formulas for these compounds.

Ethane and acetylene are two gaseous hydrocarbons. Chemical analyses show that in one sample of ethane, $2.65 \mathrm{g}$ of carbon are combined with $0.665 \mathrm{g}$ of hydrogen, and in one sample of acetylene, $4.56 \mathrm{g}$ of carbon are combined with $0.383 \mathrm{g}$ of hydrogen.
(a) Are these results consistent with the law of multiple proportions? (b) Write reasonable molecular formulas for these compounds.

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Law of Multiple Proportions

This principle states that when elements combine to form different compounds, the ratios of the masses of one element combined with a fixed mass of the other are simple whole numbers. It underpins the idea that chemical compounds are made up of discrete atoms in specific ratios, reinforcing the atomic theory of matter.

Empirical Formula Determination

This concept involves finding the simplest whole-number ratio of atoms in a compound derived from experimental mass data. By converting the masses of each element to moles and then normalizing the proportions, one can determine the empirical formula that represents the composition of the compound.

Molecular Formula Determination

Building on the empirical formula, the molecular formula represents the actual number of atoms of each element in a molecule. It often requires further information such as the compound’s molar mass and involves scaling the empirical formula by a common factor to match the experimentally determined molecular mass.

Transcript

Please give Ace some feedback