Question

Ethanoic acid is commonly known as acetic acid. It freezesdue to loss of water molecule when kept in temperature of 289.65K.does the same happen when acetic acid is dehydrated with conc H2SO4?if no why?

Answer 1

Acetic acid contains water as a solvent. At temperature 289.65 K, acetic acid loses water(solvent) molecules to form glacial acetic acid. No water molecule is lost from the acid molecule.
But when acetic acid is reacted with conc. H₂SO₄, the water molecule is lost form 2 molecules of acetic acid to form acetic anhydride.
$$\begin{gathered} {2C{H}_{3}COOH\stackrel{conc.H_{2}S{O}_4}{\to }(C{H}_{3}CO{)}_{2}O+H_{2}O}_{} \\ aceticacidaceticanhydride \end{gathered}$$

Sulphuric acid has a strong affinity for water due to which it acts as a dehydrating agent.