14 g of nitrogen represents :

Options

A. `6.02xx10^(23)N_(2)` molecules
B. 22.4 litre of `N_(2)` at 1 atm and 273 K
C. 11.2 litre of `N_(2)` at 1 atm and 273 K
D. 14 g of nitrogen

Answer

To solve the question "14 g of nitrogen represents:", we will follow these steps:

### Step 1: Determine the Molar Mass of Nitrogen
- Nitrogen gas (N₂) consists of two nitrogen atoms.
- The atomic mass of nitrogen (N) is approximately 14 g/mol.
- Therefore, the molar mass of nitrogen gas (N₂) is:
\[ \text{Molar mass of N₂} = 2 \times 14 \, \text{g/mol} = 28 \, \text{g/mol} \]

### Step 2: Calculate the Number of Moles of Nitrogen
- The number of moles (n) can be calculated using the formula:
\[ n = \frac{\text{Given mass}}{\text{Molar mass}} \]
- Substituting the values:
\[ n = \frac{14 \, \text{g}}{28 \, \text{g/mol}} = 0.5 \, \text{mol} \]

### Step 3: Calculate the Number of Molecules of Nitrogen
- The number of molecules can be calculated using Avogadro's number (approximately \(6.02 \times 10^{23}\) molecules/mol):
\[ \text{Number of molecules} = n \times \text{Avogadro's number} \]
- Substituting the values:
\[ \text{Number of molecules} = 0.5 \, \text{mol} \times 6.02 \times 10^{23} \, \text{molecules/mol} = 3.01 \times 10^{23} \, \text{molecules} \]

### Step 4: Calculate the Volume of Nitrogen at STP
- At standard temperature and pressure (STP), 1 mole of any gas occupies 22.4 liters.
- Therefore, the volume occupied by 0.5 moles of nitrogen can be calculated as:
\[ \text{Volume} = n \times 22.4 \, \text{L/mol} \]
- Substituting the values:
\[ \text{Volume} = 0.5 \, \text{mol} \times 22.4 \, \text{L/mol} = 11.2 \, \text{L} \]

### Conclusion
From the calculations, we find that:
- 14 g of nitrogen (N₂) represents 0.5 moles of nitrogen, which corresponds to approximately \(3.01 \times 10^{23}\) molecules and occupies a volume of 11.2 liters at STP.