Match (A) mole, (B) Avogadro's number, (C) 22.4 L, (D) vapour density, (E) empirical formula with its description given below.
It is the volume of one mole of a gas at STP.

Answer

To solve the question, we need to match the given terms with their correct descriptions. The description provided is: "It is the volume of one mole of a gas at STP."

Let's go through the matching step by step:

### Step 1: Understand the Terms
- **Mole**: A unit of measurement for amount of substance.
- **Avogadro's number**: The number of particles (atoms, molecules, etc.) in one mole, approximately \(6.022 \times 10^{23}\).
- **22.4 L**: The volume occupied by one mole of an ideal gas at standard temperature and pressure (STP).
- **Vapour density**: The density of a vapor compared to the density of hydrogen at the same temperature and pressure.
- **Empirical formula**: The simplest whole-number ratio of elements in a compound.

### Step 2: Analyze the Description
The description states: "It is the volume of one mole of a gas at STP."

### Step 3: Match the Term
From our understanding:
- The term that corresponds to the description "It is the volume of one mole of a gas at STP" is **(C) 22.4 L**.

### Final Answer
The correct match for the description is:
- **(C) 22.4 L**