## Chemistry: The Central Science (13th Edition)

The represented molecule is Thiourea ($C_{}H_{4}N_{2}S_{}$). 1. Find the molar mass of Thiourea: C: 12 x 1 = 12 H: 1 x 4 = 4 N: 14 x 2 = 28 S: 32 x 1 = 32 12 + 4 + 28 + 32 = 76 2. Divide the mass of carbon in one molecule by the molar mass. $\frac{12}{76}$ $\approx$ 0.1579 3. Multiply the result by 100% 0.1579 x 100% = 15.79%