Question

1. calculate the percent composition of the elements in cas.

Explanation:

Step1: Find molar masses

Molar mass of Ca: $40.08\ \text{g/mol}$; Molar mass of S: $32.07\ \text{g/mol}$
Molar mass of CaS: $40.08 + 32.07 = 72.15\ \text{g/mol}$

Step2: Calculate % Ca

$\% \text{Ca} = \frac{40.08}{72.15} \times 100 \approx 55.55\%$

Step3: Calculate % S

$\% \text{S} = \frac{32.07}{72.15} \times 100 \approx 44.45\%$

Answer:

Percent composition of Ca: ~55.55%, Percent composition of S: ~44.45%