Question

At what temperature, Na₂CO_​​3 forms monohydrate and anhydrous Na₂CO_​​3? Please answer ASAP, as tomorrow is my exam!!!!!

Answer 1

Commercial Na2CO3 most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate.

If you heat this the following occurs:

34 °C (the decahydrate decomposes to the monohydrate
100 °C the monohydrate decomposes to the anhydrous form.


Continuous heating results in the monohydrate melting at 851°C and actually boiling at 1633°C.