The density of air is `0.00130 g//ml`. The vapour density of air will be

Options

A. `0.00065`
B. `0.65`
C. `14.4816`
D. `14.56`

Explanation

To find the vapor density of air given its density, we can follow these steps:

### Step 1: Understand the relationship between density and molar mass
The vapor density (VD) of a gas is defined as half of its molar mass (M). Thus, we can express this relationship as:
\[ VD = \frac{M}{2} \]

### Step 2: Calculate the mass of 22.4 liters of air
Given the density of air is \(0.00130 \, \text{g/ml}\), we first convert this to grams per liter:
\[ 0.00130 \, \text{g/ml} = 0.00130 \times 1000 \, \text{g/L} = 1.30 \, \text{g/L} \]

Now, we calculate the mass of 22.4 liters of air:
\[ \text{Mass} = \text{Density} \times \text{Volume} = 1.30 \, \text{g/L} \times 22.4 \, \text{L} \]
\[ \text{Mass} = 1.30 \times 22.4 = 29.12 \, \text{g} \]

### Step 3: Calculate the molar mass of air
From the previous calculation, we found that the mass of 22.4 liters of air is 29.12 grams. This mass corresponds to 1 mole of air (since 22.4 L is the molar volume of a gas at standard temperature and pressure).

Thus, the molar mass (M) of air is:
\[ M = 29.12 \, \text{g/mol} \]

### Step 4: Calculate the vapor density of air
Using the relationship between molar mass and vapor density:
\[ VD = \frac{M}{2} = \frac{29.12 \, \text{g/mol}}{2} \]
\[ VD = 14.56 \, \text{g/mol} \]

### Conclusion
The vapor density of air is \(14.56 \, \text{g/mol}\).