The approximate minimum daily requirement of the amino acid leucine, C6H13NO2, is 1.1 g. How many moles is this? Use C = 12.01, H = 1.008, N = 14.007, O = 16.00 g/mol.

1. Build the molar mass of leucine from its formula. 2. Carbon contributes 6 x 12.01 = 72.06 grams per mole. 3. Hydrogen contributes 13 x 1.008 = 13.104 grams per mole. 4. Nitrogen adds 14.007 grams per mole and oxygen adds 2 x 16.00 = 32.00 grams per mole. 5. The molar mass is 72.06 + 13.104 + 14.007 + 32.00 = 131.17 grams per mole. 6. Divide the mass by the molar mass: 1.1 g / 131.17 g/mol = 0.0084 mol. 7. The value 0.0153 mol divides by the carbon subtotal of 72.06 alone, as if leucine were pure carbon. 8. The value 0.084 mol is a one decimal place slip, and 0.0042 mol halves the correct answer. _Source: OpenStax Chemistry (CC BY 4.0), Ch 3 "Composition of Substances and Solutions", section 3.1 Formula Mass and the Mole Concept_