A saccharin sample contains 1.31 x 10^20 molecules of C7H5NO3S. How many carbon atoms are present?

1. The subscript on carbon in C7H5NO3S shows seven carbon atoms in every molecule. 2. Multiply the molecule count by seven: 1.31 x 10^20 x 7. 3. The product is 9.17 x 10^20 carbon atoms. 4. The value 6.55 x 10^20 uses the five hydrogen atoms instead of the seven carbon atoms. 5. Dividing by seven instead of multiplying gives 1.87 x 10^19, which is smaller than the molecule count and so cannot be right. _Source: OpenStax Chemistry (CC BY 4.0), Ch 3 "Composition of Substances and Solutions", section 3.1 Formula Mass and the Mole Concept_