(a) What is glacial acid and why is it called so ?
(b) What is vinegar and how is it prepared ?
( c) The experimentally determined (by colligative properties method) molecular weight of acetic acid in the vapour state is `120`. Explain why.

Explanation

Completely pure `(100%)` acetic acid is known as glacial acetic acid. The melting point of anhydrous acid is `17(@)C`. It is a solid below this temperature and has an icy look. It therefore, looks like a glacial.