Question

What's the percent composition of sulfur in H2SO4?
Question 3 options:

A)

98.1%

B)

2.1%

C)

65.2%

D)

32.7%

Answer 1

To find the percent composition of sulfur in sulfuric acid (H₂SO₄), we need to calculate the molar mass of H₂SO₄ and the mass contribution of sulfur.

1. **Calculate the molar mass of H₂SO₄:**
- Hydrogen (H): 1.01 g/mol (2 H atoms) → 2 × 1.01 = 2.02 g/mol
- Sulfur (S): 32.07 g/mol (1 S atom) → 32.07 g/mol
- Oxygen (O): 16.00 g/mol (4 O atoms) → 4 × 16.00 = 64.00 g/mol

Now, add them together:
\[
\text{Molar mass of H₂SO₄} = 2.02 + 32.07 + 64.00 = 98.09 \text{ g/mol}
\]

2. **Calculate the percent composition of sulfur:**
- Mass of sulfur = 32.07 g/mol
- Molar mass of H₂SO₄ = 98.09 g/mol

Now, calculate the percent:
\[
\text{Percent sulfur} = \left( \frac{\text{mass of sulfur}}{\text{molar mass of H₂SO₄}} \right) \times 100 = \left( \frac{32.07}{98.09} \right) \times 100 \approx 32.65\%
\]

Therefore, the percent composition of sulfur in H₂SO₄ is approximately 32.7%.

Thus, the correct answer is:

**D) 32.7%**