Determine the percentage of oxygen in ammonium nitrite

Explanation

To determine the percentage of oxygen in ammonium nitrite (NH4NO2), we will follow these steps:

### Step 1: Identify the molecular formula of ammonium nitrite.
The molecular formula for ammonium nitrite is NH4NO2.

### Step 2: Determine the number of oxygen atoms in the compound.
In NH4NO2, there are 2 oxygen atoms.

### Step 3: Calculate the mass of oxygen in the compound.
The atomic mass of oxygen (O) is approximately 16 g/mol. Therefore, the mass of 2 oxygen atoms is:
\[ \text{Mass of oxygen} = 2 \times 16 = 32 \text{ g/mol} \]

### Step 4: Calculate the molecular mass of ammonium nitrite.
To find the molecular mass of NH4NO2, we need to sum the atomic masses of all the atoms in the formula:
- Nitrogen (N): 14 g/mol (2 nitrogen atoms)
- Hydrogen (H): 1 g/mol (4 hydrogen atoms)
- Oxygen (O): 16 g/mol (2 oxygen atoms)

Calculating the total:
\[ \text{Molecular mass} = (2 \times 14) + (4 \times 1) + (2 \times 16) = 28 + 4 + 32 = 64 \text{ g/mol} \]

### Step 5: Calculate the percentage of oxygen in ammonium nitrite.
Using the formula for percentage by mass:
\[ \text{Percentage of oxygen} = \left( \frac{\text{Mass of oxygen}}{\text{Molecular mass of compound}} \right) \times 100 \]
Substituting the values:
\[ \text{Percentage of oxygen} = \left( \frac{32}{64} \right) \times 100 = 50\% \]

### Final Answer:
The percentage of oxygen in ammonium nitrite is **50%**.

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