Question

Thermal decomposition of a metal oxalate question:

A metal oxalate was synthesized by vacuum filtration. Afterwards, the DRY metal oxalate product undergoes thermal decomposition. 0.990-1.010g of oxalate product is placed on a hotplate and heated to 275C for 10 minutes, increased to 400C for another 10 minutes, and allowed to cool. The mass is determined and the process of heating and reweighing is repeated until two successive trials do not differ by more than 0.010g and the product looks homogenous in color.

Question: If the metal oxalate product was not as dry as possible (a little wet) at the start of the thermal decomposition, how might this affect the thermal decomposition procedure? How might the mass be affected?

Answer 1

Solution :-

If the metal oxalate is not dry then mass of the metal oxalate measured will be less than actual mass because the wet metal oxalate contains the water which will add up to the mass of the metal oxalate and when the heating process is started then water will be evaporated which will give the less mass of the desired products. So this will give the less percent yield of the product. Also there might be the change that it can undergo the chemical change and form unwanted products. So it is important that the metal oxalate must be dry at the beginning of the heating of the metal oxalate.