Question

extra practice

1. a compound contains 12 grams sulfur and 18 grams oxygen. what is the empirical formula?

Explanation:

Step1: Calculate moles of sulfur

Molar mass of sulfur (\(S\)) is \(32\space g/mol\). Moles of \(S=\frac{12\space g}{32\space g/mol}=\frac{3}{8}\space mol\)

Step2: Calculate moles of oxygen

Molar mass of oxygen (\(O\)) is \(16\space g/mol\). Moles of \(O = \frac{18\space g}{16\space g/mol}=\frac{9}{8}\space mol\)

Step3: Find mole ratio

Divide each mole value by the smaller mole value (\(\frac{3}{8}\)). For \(S:\frac{\frac{3}{8}}{\frac{3}{8}} = 1\). For \(O:\frac{\frac{9}{8}}{\frac{3}{8}}=3\)

Answer:

\(SO_{3}\)