Question

The number of gram molecules of a substance present in unit volume is termed as:

• A. Activity
• B. Normal solution
• C. Molar concentration
• D. Active mass

Hint:

Molarity (M) is defined as the number of moles of solute per liter of solution and is very useful in reactions, where we’re using moles to balance the reactions. However, molarity changes with temperature due to changes in volume, and molality is preferred in that case.

Answer 1

The Correct Option is C

Molarity, or molar concentration, quantifies the moles of solute contained within 1 liter of solution. It is expressed as:
\(M = \frac{\text{moles of solute}}{\text{volume of solution (L)}}\)
This concept is essential for stoichiometry and solution preparation. Related terms include:
Activity: The effective concentration of a species in solution.
Normal solution: A solution with concentration in equivalents per liter.
Active mass: An obsolete term for concentration in reaction rate expressions.