Question

what happens when H3PO4 is heated​

Answer 1

When pure phosphoric acid is heated, two molecules may condense (release water from a reaction between them) to form a polyphosphoric acid.

ok bro

follow me

thanks

Answer 2

Orthophosphoric acid or H3PO4 when heated to a temperature of 250 ∘ C yields pyrophosphoric acid and water as products of its reaction. The heating of orthophosphoric acid to 316 ∘ C or the heating of pyrophosphoric acid to 316 ∘ C yields metaphosphoric acid and water as products of the reaction.