Question

What feature related to the composition of a compound can be determined solely by percent composition?

Short answer

The feature related to the composition of a compound that can be determined solely by percent composition is its empirical formula. This represents the simplest ratio of atoms or moles of each element in the compound.

Step-by-step solution

Understand percent composition

Knowing the percent composition of a compound allows you to determine the ratios in which elements combine to form compounds. This includes the ratio of atoms or moles of each element in the compound.

Identify the feature

So, with the values provided by the percent composition, you can deduce the empirical formula of the compound, which is the simplest positive integer ratio of atoms present in a compound.

Conclude

In conclusion, the empirical formula of a compound can be determined by its percent composition. Using this formula, we are able to understand the ratio of atoms or moles in a compound.

Key concepts

Empirical Formula

The empirical formula is the simplest representation of a compound's composition. It denotes the smallest whole number ratio of elements in a molecule. Unlike the molecular formula, which indicates the actual number of each type of atom in a molecule, the empirical formula is purely a ratio and does not reflect the actual quantity. For instance, hydrogen peroxide's molecular formula is H₂O₂, but its empirical formula is simply HO, which shows the one-to-one ratio of hydrogen to oxygen atoms.

Understanding the empirical formula is crucial because it is the first step in deducing the molecular formula of a compound, which can then be utterly beneficial in determining the chemical structure and properties of the substance. To determine an empirical formula from percent composition, one should convert the percentage to mass, to moles, and then find the simplest ratio between the moles of each element involved.

Chemical Composition

Chemical composition refers to the arrangement, type, and ratio of atoms in molecules of chemical substances. It can be specified using a variety of terms, such as empirical or molecular formulas. Chemical composition can be qualitative, indicating which elements are present in a compound, or quantitative, noting how much of each element exists in the substance.

Percent composition is a quantitative measure and a key concept in determining the chemical composition. It represents the percentage by mass of each element in a compound. Knowing the percent composition is essential for chemists to identify the compound and its properties. For example, if a compound is 40% carbon, 6.7% hydrogen, and 53.3% oxygen by mass, these numbers can help us to infer the empirical formula and thus depict the chemical composition of the substance.

Mole Ratio

The mole ratio is a term frequently used in chemistry to represent the ratio of moles of one substance to the moles of another substance in a chemical reaction. It is derived directly from the coefficients in a balanced chemical equation and is essential in stoichiometric calculations.

Mole ratios can assist with converting between moles of reactants and products, which allows chemists to calculate the amounts of substances consumed and produced in a reaction. The mole ratio is also pivotal when determining the empirical formula. By converting the mass percentages into moles, we can then use the mole ratio of elements to find the simplest whole number ratio of elements. This ratio expresses the empirical formula, which is a fundamental step in deducing the compound's molecular structure and chemical behavior.