Write the chemical equation to convert acetic acid to monochloro acetic acid. Name this reaction. 

Explanation

`underset("(Ethanoic acid)")(CH_(3)COOH) overset("i) "Cl_(2),"Red P")underset("ii) "H_(2)O)rarr underset("2 - Chloro ethanoic acid")(underset(Cl)underset(|)CH_(2)-COOH)`
Carboxylic acids containing `alpha-`hydrogen reacts with chlorine OR bromine in the presence of small quantities of red phosphorus to form `alpha-`halo acids. This reaction is called Hell-Valhard-Zelinsky.s reaction.