Which of the following is a way to express the concentration of a solution?

• A. Density (g/cm^3)
• B. Pressure (atm)
• C. Molarity (mol/L)
• D. Boiling point (°C)

Answer: (C)

Verified step by step guidance

1. Understand that concentration refers to the amount of solute present in a given quantity of solvent or solution.
2. Recognize that common ways to express concentration include molarity (mol/L), molality (mol/kg), mass percent, and mole fraction.
3. Identify that density (g/cm^3) is a physical property related to mass and volume, but it does not directly express concentration of solute in solution.
4. Note that pressure (atm) and boiling point (°C) are physical properties influenced by concentration but are not direct measures of concentration themselves.
5. Conclude that molarity, defined as the number of moles of solute per liter of solution, is a standard and direct way to express concentration.