The compounds C₂H₂ and C₆H₆ have the same percent composition by mass.

Question

Quizplus · Accepted Answer

Since the compounds have the same percent composition by mass, it means that the ratio of the masses of each element in the compounds is the same. Thus, the subscripts (or number of atoms) for each element in each compound must also be the same. Therefore, both compounds have the same subscripts for each element, and thus have the same chemical formula.

The Compounds C2H2 and C6H6 Have the Same Percent Composition

The Compounds C₂H₂ and C₆H₆ Have the Same Percent Composition