M(propenoic acid - C₃H₄O₂) = 72 g/mol.
ω(C) = M(C) ÷ M(C₃H₄O₂) · 100%.
ω(C) = 3 · 12 g/mol ÷ 72 g/mol · 100%.
ω(C) = 36 g/mol ÷ 72 g/mol · 100%.
ω(C) = 50%.
ω(H) = M(H) ÷ M(C₃H₄O₂) · 100%.
ω(H) = 4 · 1 g/mol ÷ 72 g/mol · 100%.
ω(H) = 4 g/mol ÷ 72 g/mol · 100%.
ω(H) = 5,55 %.