Determine the empirical formula for a compound that is 36.86% N and 63.14% O by mass.

• A. N2O5
• B. NO2
• C. NO
• D. N2O3

Answer: (D)

Verified step by step guidance

1. Convert the percentage of each element to grams. Assume you have 100 grams of the compound, so you have 36.86 grams of nitrogen (N) and 63.14 grams of oxygen (O).
2. Convert the mass of each element to moles by dividing by their respective molar masses. Use the molar mass of nitrogen (N) as 14.01 g/mol and oxygen (O) as 16.00 g/mol. Calculate the moles of nitrogen: \( \frac{36.86 \text{ g}}{14.01 \text{ g/mol}} \) and the moles of oxygen: \( \frac{63.14 \text{ g}}{16.00 \text{ g/mol}} \).
3. Determine the simplest whole number ratio of moles of each element by dividing each by the smallest number of moles calculated in the previous step.
4. If necessary, multiply the ratios by a common factor to obtain whole numbers. This step ensures that the empirical formula is expressed in the simplest whole number ratio.
5. Write the empirical formula using the whole number ratios as subscripts for each element. The empirical formula is the simplest ratio of the elements in the compound.