Refer to the figure to answer questions 4 and 5. The images are a molecular representation of three different substances, AX3, AY3, and AZ3, dissolved in water. (Water molecules are omitted for clarity.) What are the molar concentrations of A ions and X ions in a 0.500 M solution of AX3? (LO 4.7) (a) 0.500 M A and 0.500 M X (b) 0.500 M A and 0.167 M X (c) 1.500 M A and 0.500 M X (d) 0.500 M A and 1.500 M X

Key Concepts

Molarity

Molarity is a measure of concentration defined as the number of moles of solute per liter of solution. It is expressed in moles per liter (M). Understanding molarity is crucial for calculating the concentrations of ions in a solution, especially when dealing with ionic compounds that dissociate in water.

Dissociation of Ionic Compounds

When ionic compounds dissolve in water, they dissociate into their constituent ions. For example, a compound AX3 will dissociate into one A ion and three X ions. This dissociation is essential for determining the molar concentrations of the individual ions in a solution, as it directly affects the total concentration of each ion present.

Stoichiometry of Dissolution

Stoichiometry involves the quantitative relationships between the amounts of reactants and products in a chemical reaction. In the context of dissolution, it helps in calculating the concentrations of ions based on the stoichiometric coefficients from the dissociation equation. For AX3, the stoichiometry indicates that for every mole of AX3, one mole of A and three moles of X are produced, guiding the concentration calculations.