Final answer:
The chemical equation for the burning of magnesium in oxygen is 2Mg(s) + O2(g) → 2MgO(s), and for the decomposition of calcium carbonate, it is CaCO3(s) → CaO(s) + CO2(g).
Step-by-step explanation:
The chemical equation for the reaction of burning of magnesium in oxygen can be written as:
2Mg(s) + O2(g) → 2MgO(s)
For the decomposition of calcium carbonate, the reaction can be represented as follows:
CaCO3(s) → CaO(s) + CO2(g)
The decomposition of calcium carbonate into calcium oxide and carbon dioxide can be induced by heating. In each case, the reactant(s) and product(s) are shown with their appropriate physical states.