Question Detail
Question
What is the number of moles present in a 159 g sample of alanine C₃H₇NO₂? [C=12, H=1, N=14, O=16].
Correct Answer
Option D is the correct answer.
Detailed Explanation
Molar mass of C₃H₇NO₂ = (3×12)+(7×1)+14+(2×16)=36+7+14+32=89 g/mol. Moles = 159 g / 89 g/mol = 1.7865 ≈ 1.79 mol.
Hint
Moles = mass / molar mass.