Which term describes the amount of substance contained in one liter of solution?

Molarity is the correct term for the amount of substance contained in one liter of solution. Specifically, molarity is defined as the number of moles of solute per liter of solution. It is a commonly used concentration unit in chemistry that helps quantify how much solute is dissolved in a given volume of solvent. This unit allows chemists to easily compare concentrations and perform calculations related to reactions in solution.

To understand why molarity fits best here, it is essential to consider how it is calculated: if you have 1 mole of a substance dissolved in 1 liter of solution, you have a molarity of 1 M (1 mole per liter). This direct relationship makes molarity a critical concept for stoichiometric calculations in chemical reactions.

Density refers to mass per unit volume and is not specifically concerned with the amount of solute relative to the total volume of solution. Concentration is a broader term that can encompass various ways to express the amount of solute in a solution but does not specify units, while "moles per volume" is less commonly used as it lacks the concise definition provided by molarity. Therefore, molarity is the most precise term for quantifying solute concentration in the context of a solution.