Question

The rate at which a substance reacts depends upon its:

• A. Active mass
• B. Atomic mass
• C. Molecular mass
• D. Equivalent mass

Answer 1

The correct option is A

Active mass

Explanation of the correct answer:

The correct answer is option A:

1. The concentration of a reactive material, given typically in moles per litre, is known as active mass.
2. Since the rate of reaction is directly proportional to the concentration of each reactant and product, the rate at which a material reacts relies on its active mass.

Explanation of the incorrect answers:

Option B:

1. The mass of each isotope is multiplied by its abundance to get the atomic mass, which is a weighted average of all the isotopes of that element.

Option C:

1. The total mass of the constituent components in a molecule is known as the element's molecular mass.

Option D:

1. The mass of one equivalent commonly referred to as the gram equivalent is the mass of a particular material that will mix with or replace a certain amount of another substance.

Hence, option (A) is correct, i.e., Active mass.