Which of the following pairs of compounds do NOT have the same empirical formula?

• A. C2H2 and C6H6
• B. C6H12O6 and C2H4O2
• C. C4H10 and C2H6
• D. C2H4 and C3H6

Answer: (C)

Verified step by step guidance

1. Recall that the empirical formula represents the simplest whole-number ratio of atoms of each element in a compound.
2. For each pair of compounds, determine the empirical formula by dividing the subscripts of each element by their greatest common divisor (GCD).
3. For example, for C2H2, the GCD of 2 and 2 is 2, so the empirical formula is C1H1 (or CH). For C6H6, the GCD of 6 and 6 is 6, so the empirical formula is also CH. This means C2H2 and C6H6 have the same empirical formula.
4. Repeat this process for each pair: find the GCD of the subscripts in each compound, divide the subscripts by the GCD, and compare the resulting empirical formulas.
5. Identify the pair whose empirical formulas differ after simplification; that pair does NOT have the same empirical formula.