What is the mass percent of oxygen (O) in SO₂?

A. [tex]\(\frac{(16.0 \, \text{g} + 16.0 \, \text{g}) \left(6.02 \times 10^{23}\right)}{100 \, \text{g}}\)[/tex]

B. [tex]\(\frac{16.0 \, \text{g}}{(32.1 \, \text{g} + 16.0 \, \text{g} + 16.0 \, \text{g})} \times 100 \%\)[/tex]

C. [tex]\(\frac{(16.0 \, \text{g} + 16.0 \, \text{g})}{(32.1 \, \text{g} + 16.0 \, \text{g} + 16.0 \, \text{g})} \times 100 \%\)[/tex]

D. [tex]\(\frac{32.1 \, \text{g}}{16.0 \, \text{g} + 16.0 \, \text{g}} \times 100 \%\)[/tex]



Answer :

To determine the mass percent of oxygen in sulfur dioxide (SO₂), follow these steps:

1. Calculate the Molar Mass of SO₂:
- The atomic mass of sulfur (S) is 32.1 g/mol.
- The atomic mass of oxygen (O) is 16.0 g/mol.
- Since each molecule of SO₂ contains one sulfur atom and two oxygen atoms, its total molar mass is:
[tex]\[ 32.1 \, \text{g} (\text{S}) + 16.0 \, \text{g} (\text{O}) + 16.0 \, \text{g} (\text{O}) = 64.1 \, \text{g/mol} \][/tex]

2. Calculate the Total Mass of Oxygen in SO₂:
- Each SO₂ molecule contains two oxygen atoms.
- Therefore, the total mass of oxygen in one molecule of SO₂ is:
[tex]\[ 16.0 \, \text{g} (\text{O}) + 16.0 \, \text{g} (\text{O}) = 32.0 \, \text{g} \][/tex]

3. Calculate the Mass Percent of Oxygen in SO₂:
- The mass percent formula is given by:
[tex]\[ \text{Mass Percent} = \left( \frac{\text{Mass of Component}}{\text{Total Mass of Compound}} \right) \times 100 \% \][/tex]
- Substituting in the values for the mass of oxygen and the total mass of SO₂:
[tex]\[ \text{Mass Percent of Oxygen} = \left( \frac{32.0 \, \text{g}}{64.1 \, \text{g}} \right) \times 100 \% \approx 49.92 \% \][/tex]

4. Identify the Correct Answer Option:
- From the given options, option C matches our detailed calculations, expressing the mass percent of oxygen correctly:
[tex]\[ \frac{(16.0 \, \text{g} + 16.0 \, \text{g})}{(32.1 \, \text{g} + 16.0 \, \text{g} + 16.0 \, \text{g})} \times 100 \% \][/tex]

Thus, the correct answer is [tex]\( \boxed{C} \)[/tex].