A compound contains 50% sulfur and 50% oxygen by mass. What is its empirical formula?

• A. S_2O_2
• B. S_2O
• C. SO_2
• D. SO

Answer: (D)

Verified step by step guidance

1. Step 1: Assume a 100 g sample of the compound to simplify calculations. This means you have 50 g of sulfur (S) and 50 g of oxygen (O).
2. Step 2: Convert the masses of each element to moles using their molar masses. Use the molar mass of sulfur as approximately 32.07 g/mol and oxygen as approximately 16.00 g/mol. Calculate moles of sulfur as \(\frac{50}{32.07}\) and moles of oxygen as \(\frac{50}{16.00}\).
3. Step 3: Determine the mole ratio by dividing both mole values by the smaller number of moles obtained in Step 2. This will give you the simplest whole number ratio of atoms in the compound.
4. Step 4: If the mole ratio is not a whole number, multiply both ratios by the smallest factor that converts them into whole numbers. This step ensures the empirical formula uses whole number subscripts.
5. Step 5: Write the empirical formula using the whole number mole ratios as subscripts for sulfur and oxygen. For example, if the ratio is 1:1, the empirical formula is SO.