28. Which of the following could be an empirical formula?
Answer: C
CH could be an empirical formula.
An empirical formula represents the simplest whole-number ratio of elements in a compound. The formula CH indicates that for every carbon atom, there is one hydrogen atom, which is a valid representation of a compound's composition in its simplest form.
A) C4H8
C4H8 can be simplified to C1H2, which suggests that it does not represent the simplest ratio of the elements. While it is a molecular formula, it does not qualify as an empirical formula since it can be reduced further.
B) C2H6
C2H6 can also be simplified to C1H3, indicating that it does not represent the simplest form of the ratio of carbon to hydrogen. Therefore, while it describes a valid compound, it does not qualify as an empirical formula.
C) CH
CH represents the simplest whole-number ratio of carbon to hydrogen, with one carbon atom for every hydrogen atom. Thus, it stands as an empirical formula without any potential for further simplification.
D) C3H6
C3H6 can be simplified to C1H2, which means it does not represent the simplest ratio of the elements. Although it is a valid molecular formula, it fails to qualify as an empirical formula since it can be reduced.
Conclusion
The formula CH is definitively the correct answer because it accurately represents the simplest ratio of elements in a compound. In contrast, all other options can be simplified further, indicating they do not meet the criteria for empirical formulas. This highlights the importance of identifying the simplest ratio in determining empirical formulas.