The molecular mass of methyl ethanoate is 74.1 amu . calculate the molecular mass of propanoic acid, an isomer of methyl ethanoate. express your answer with the appropriate units.

Isomers are the compounds having same molecular formula but different structural formula. 

Since, molecular formula is isomers are same, they have same mass.

Now, methyl ethanoate is  an isomer of propanoic acid, hence they have same mass.

∴ Molecular mass of propanoic acid = 74.1 amu or 74.1 g/mol

I’m pretty sure it’s false i’m not sure