The number of moles of nitrogen present in one litre of air containing 17% nitrogen by volume, under standard condition, is:

Options

A. 6.73 x `10^(-3)`
B. 4.03 x `10^(-3)`
C. 7.58 x `10^(-3)`
D. 5.83 x `10^(-3)`

Explanation

To find the number of moles of nitrogen present in one liter of air containing 17% nitrogen by volume under standard conditions, we can follow these steps:

### Step-by-step Solution:

1. **Determine the Volume of Nitrogen:**
Given that nitrogen constitutes 17% of the air by volume, we can calculate the volume of nitrogen in 1 liter of air.
\[ \text{Volume of Nitrogen} = 17\% \text{ of 1 L} = \frac{17}{100} \times 1 \text{ L} = 0.17 \text{ L} \]

2. **Use the Ideal Gas Law:**
Under standard temperature and pressure (STP), 1 mole of an ideal gas occupies 22.4 liters. We can use this information to find the number of moles of nitrogen in the calculated volume.
\[ \text{Number of moles of Nitrogen} = \frac{\text{Volume of Nitrogen}}{\text{Volume occupied by 1 mole at STP}} = \frac{0.17 \text{ L}}{22.4 \text{ L/mole}} \]

3. **Calculate the Number of Moles:**
Now, we perform the calculation:
\[ \text{Number of moles of Nitrogen} = \frac{0.17}{22.4} \approx 0.007577 \text{ moles} \]

4. **Express in Scientific Notation:**
To express this in scientific notation:
\[ 0.007577 \text{ moles} \approx 7.58 \times 10^{-3} \text{ moles} \]

5. **Final Answer:**
Therefore, the number of moles of nitrogen present in one liter of air containing 17% nitrogen by volume under standard conditions is:
\[ \boxed{7.58 \times 10^{-3} \text{ moles}} \]