Reaction of gaseous fluorine with compound X yields a single product Y, whose mass percent composition is 61.7% F and 38.3% Cl. (a) What is a probable molecular formula for product Y, and what is a probable formula for X?

Key Concepts

Mass Percent Composition

Mass percent composition refers to the percentage by mass of each element in a compound. It is calculated by dividing the mass of the element in one mole of the compound by the molar mass of the compound, then multiplying by 100. Understanding mass percent is crucial for determining the empirical and molecular formulas of compounds based on their elemental composition.

Empirical and Molecular Formulas

The empirical formula represents the simplest whole-number ratio of elements in a compound, while the molecular formula indicates the actual number of atoms of each element in a molecule. To derive the molecular formula from mass percent composition, one first determines the empirical formula and then uses the molar mass to find the molecular formula, which may be a multiple of the empirical formula.

Stoichiometry of Chemical Reactions

Stoichiometry involves the calculation of reactants and products in chemical reactions based on the conservation of mass. In this context, knowing the reactants (gaseous fluorine and compound X) and the product (compound Y) allows for the application of stoichiometric principles to deduce the likely formulas of X and Y, ensuring that the reaction balances in terms of both mass and moles.