Question

Which of the following variables are needed to calculate molarity?

• A. weight of solvent
• B. temperature
• C. No. of moles
• D. none

Answer 1

The correct option is C

No. of moles

Avogadro's constant will be required if a question gives you the number of particles / ions etc., of the solute to calculate number of moles.

Gas constant may be required if the temperature and pressure conditions of a gas are provided to calculate the volume and use that to calculate number of moles in case the gas is later used as a solute.

Number of moles and volume of solution are obviously required.