Question

Which compound is an isomer of propanoic acid (CH3CH2COOH)?

A) CH2CHCOOH
B) CH3CH2CH2COOH
C) CH3CH(OH)CH2OH
D) HCOOCH2CH3

Answer 1

D) HCOOCH2CH3

Step-by-step explanation:

Option D is an isomer of propanoic acid because this compound has the same number of atoms as the acid; 3 carbons, 6 hydrogens and 2 oxygen. They may differ in some properties but their main difference must be their molecular structure, that is, the arrangement of their atoms.

Answer 2

D) HCOOCH2CH3

Step-by-step explanation:

An isomer of a compound is defined as a chemical substances with the same formula (That is, same atoms) but in different structures.

For propanoic acid, there are 3 atoms of C, 6 atoms of H and 2 atoms of oxygen.

A) CH2CHCOOH . Here you have 3 atoms of C but 4 atoms of H. That means this compound is not an isomer.

B) CH3CH2CH2COOH . Here, there are 4 atoms of C. Thus, is not an isomer.

C) CH3CH(OH)CH2OH. This structure has 3 atoms of C, but 8 atoms of H. Thus, is not an isomer.

D) HCOOCH2CH3. Here, there are 3 atoms of C, 6 atoms of H and 2 atoms of O. Thus, this structure is an isomer of propanoic acid.