To determine the percent composition of sulfur (S) in copper(II) sulfate (CuSO₄), follow these steps:
1. Identify the molar masses of the individual elements:
- The molar mass of copper (Cu) is 63.55 g/mol.
- The molar mass of sulfur (S) is 32.07 g/mol.
- The molar mass of oxygen (O) is 16.00 g/mol.
2. Calculate the molar mass of CuSO₄:
- The formula for CuSO₄ includes one atom of copper (Cu), one atom of sulfur (S), and four atoms of oxygen (O).
- Therefore, the molar mass of CuSO₄ is calculated as follows:
[tex]\[
\text{Molar mass of CuSO}_4 = \text{Molar mass of Cu} + \text{Molar mass of S} + 4 \times \text{Molar mass of O}
\][/tex]
Substituting the given molar masses:
[tex]\[
\text{Molar mass of CuSO}_4 = 63.55\, \text{g/mol} + 32.07\, \text{g/mol} + 4 \times 16.00\, \text{g/mol}
\][/tex]
[tex]\[
\text{Molar mass of CuSO}_4 = 63.55 + 32.07 + 64.00 = 159.62\, \text{g/mol}
\][/tex]
3. Calculate the percent composition of sulfur in CuSO₄:
- The percent composition of an element within a compound is calculated using the formula:
[tex]\[
\% \text{ of S} = \left( \frac{\text{Molar mass of S}}{\text{Molar mass of CuSO}_4} \right) \times 100
\][/tex]
Substituting the molar masses:
[tex]\[
\% \text{ of S} = \left( \frac{32.07\, \text{g/mol}}{159.62\, \text{g/mol}} \right) \times 100
\][/tex]
[tex]\[
\% \text{ of S} \approx 20.09\%
\][/tex]
Therefore, the percent composition of sulfur (S) in CuSO₄ is approximately [tex]\( 20.09\% \)[/tex].
