Ammonium Thioglycolate

Ammonium thioglycolate, also known as perm salt, is the chemical compound with the formula HSCH₂CO₂NH₄.

Being the salt of a weak acid and weak base, ammonium thioglycolic acid exists in solution as an equilibrium mixture of the salt itself as well as the free carboxylic acid thioglycolic acid (HSCH₂CO₂H) and ammonia:

HSCH₂COO− + NH₄+ ⇌ HSCH₂COOH + NH₃