Question

Assertion (A): All pure substances are homogeneous.

Reason (R): Pure substances are made up of only one kind of molecule and they are uniformly distributed.

• A. Both A and R are true and R is the correct explanation of A.
• B. Both A and R are true, but R is not the correct explanation of A.
• C. A is true and R is false.
• D. A is false and R is true.

Answer 1

The correct option is A

Both A and R are true and R is the correct explanation of A.

Explanation for Assertion statement:

1. Homogeneous refers to something that is the same or uniform throughout.
2. A homogenous substance can therefore be either a mixture or a pure substance.
3. When a homogeneous substance contains the same type of molecule throughout with a stable and consistent composition, the substance is said to be pure.

Explanation for Reason statement:

1. A substance made up of only one type or sort of atom is referred to as an element.
2. An element is a pure material since it cannot be broken down or changed into a different substance by physical or chemical means.
3. Metals, non-metals, and metalloids are the most common elements.

Conclusion: Both A and R are true and R is the correct explanation of A. Hence, option (A) is correct.