The percentage of nitrogen in `HNO_(3)` is

Options

A. 0.2222
B. 0.35
C. 0.2857
D. 0.45

Answer

To find the percentage of nitrogen in HNO₃ (nitric acid), we will follow these steps:

### Step 1: Calculate the molar mass of HNO₃
- The molar mass of HNO₃ can be calculated by adding the atomic masses of its constituent elements:
- Hydrogen (H): 1 g/mol
- Nitrogen (N): 14 g/mol
- Oxygen (O): 16 g/mol (and there are 3 oxygen atoms in HNO₃)

\[ \text{Molar mass of HNO}_3 = (1 \times 1) + (1 \times 14) + (3 \times 16) = 1 + 14 + 48 = 63 \text{ g/mol} \]

### Step 2: Identify the mass of nitrogen in HNO₃
- The mass of nitrogen in HNO₃ is simply the atomic mass of nitrogen, which is 14 g/mol.

### Step 3: Calculate the percentage of nitrogen in HNO₃
- The percentage of nitrogen can be calculated using the formula:

\[ \text{Percentage of nitrogen} = \left( \frac{\text{mass of nitrogen}}{\text{molar mass of HNO}_3} \right) \times 100 \]

Substituting the values we have:

\[ \text{Percentage of nitrogen} = \left( \frac{14}{63} \right) \times 100 \]

### Step 4: Perform the calculation
\[ \text{Percentage of nitrogen} = \left( 0.2222 \right) \times 100 = 22.22\% \]

### Final Answer
The percentage of nitrogen in HNO₃ is **22.22%**.

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