We need to calculate the ratio of C to H in the molecule: We have 3 C and 8 H, so the ratio is 3:8 If we have 10.0 moles C, we divide that by the number of C atoms to get the factor: 10/3 = 3.33 The we multiply the number of H atoms, 8, by this factor: 3.33 x 8 = 26.67 So we have 10.0 moles of C and 26.67 moles of H for a total of 36.67 moles in the sample.
