Question

Why is pure acetic acid known as glacial acetic acid?

Answer 1

To know why pure acetic acid known as glacial acetic acid, first we should discuss the reason behind why we call pure acetic acid ass glacial acetic acid. And then we will also discuss more about the acetic acid.

Complete answer:
Pure acetic acid is known as glacial acetic acid because acetic acid on reaching the melting point forms a glacier and thus glacial acetic acid. Pure ethanoic acid is called glacial ethanoic acid because it solidifies just below room temperature, at $16.7^\circ C$.
Acetic acid $(C{H_3}COOH)$ is the common name for ethanoic acid. It is an organic chemical compound that has a distinctive pungent odor and sour flavour, recognizable as the scent and flavor of vinegar. Vinegar is about $3 - 9\%$ acetic acid.
Acetic acid that contains an extremely low measure of water (under $1\%$) is called anhydrous (sans water) Acetic acid or cold Acetic acid. The explanation it's called frigid on the grounds that it sets into strong acidic corrosive precious stones only cooler than room temperature at $16.7{\text{ }}^\circ C$ , which is ice. Eliminating the water from Acetic acid brings down its dissolving point by $0.2{\text{ }}^\circ C$.
Frigid Acetic acid might be set up by trickling Acetic acid arrangement over a "underground rock formation" of strong Acetic acid (which could be viewed as frozen). Like a water ice sheet contains decontaminated water, regardless of whether it's skimming in the pungent ocean, unadulterated acidic corrosive adheres to the frigid Acetic acid, while contaminations escape with the fluid.

Note:
Acetic acid has an acidic character because the hydrogen centre in the carboxyl group $- COOH$ separates via ionization to release a proton: This makes acetic acid a monoprotic acid with a $pKa$ value of 4.76 in aqueous solution.