Answer:
The crucible will gain mass upon heating due to the formation of new compounds like oxides
Explanation:
The increase in mass of the crucible and its contents upon heating can be attributed to the formation of new compounds specifically oxides.
For example when a piece of magnesium placed in a crucible is heated and then weighed, there would be an increase mass. This is due to the reaction of magnesium (Mg) with air (O2) resulting in the formation of magnesium oixide (MgO) as per the following equation:
[tex]2Mg(s) + O_{2}(g)\rightarrow 2MgO(s)[/tex]
