The other day I was cooking milk rice and forgot about it so it burned a little on the bottom. This lower layer was very hard to clean. A lot of websites recommend boiling water in the pot with baking soda (Sodium bicarbonate) or citric acid to dissolve the burned residue and make it easier to clean the pot. I tried this but it did not help. I doubt there is even a chemical reaction between these reagents that would help in any way.
Is this another myth or is there scientific basis for given recommendation?