Assertion (A): Vapour pressure increase with increase in temperature.
Reason (R): With increase in temperature, more molecules of the liquid can go into vapour phase.

Options

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 but R is false
D. A is false and R is True

Explanation

To solve the question regarding the assertion and reason about vapor pressure and temperature, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that "Vapor pressure increases with an increase in temperature."
- This is a well-established principle in physical chemistry. As temperature rises, the kinetic energy of the molecules in a liquid also increases.

**Hint:** Consider how temperature affects molecular motion and energy.

### Step 2: Analyze the Reason
The reason given is "With an increase in temperature, more molecules of the liquid can go into the vapor phase."
- This statement is also true. As the temperature increases, more molecules gain enough energy to overcome the intermolecular forces holding them in the liquid state, allowing them to escape into the vapor phase.

**Hint:** Think about the relationship between molecular energy and phase changes.

### Step 3: Connect the Assertion and Reason
Now, we need to determine if the reason correctly explains the assertion.
- The increase in vapor pressure due to temperature rise is indeed due to more molecules transitioning to the vapor phase. Therefore, the reason supports the assertion.

**Hint:** Reflect on how one statement logically leads to the other.

### Step 4: Conclusion
Since both the assertion and reason are true, and the reason correctly explains the assertion, we can conclude:
- Both A and R are true, and R is the correct explanation of A.

**Final Answer:** Option 1: Both A and R are true, and R is the correct explanation of A.