Question

0.5 moles of monoalkanoic acid weighs 44g. Determine the molecular formula and the name of the acid.

a) CH3COOH (Acetic Acid)
b) C2H4O2 (Formic Acid)
c) C3H6O3 (Lactic Acid)
d) C4H8O4 (Tartaric Acid)

Answer 1

The molecular formula of the monoalkanoic acid is CH3COOH (acetic acid).

Step-by-step explanation:

The molecular formula for the given monoalkanoic acid is C2H4O2 or CH3COOH. This can be determined by comparing the molar mass of the empirical formula (CH2O) with the given molar mass of 44g. As the molar mass of the empirical formula is half of the given molar mass, the actual number of moles of each element in the molecular formula is double compared to the empirical formula.