Final answer:
The reaction where calcium carbonate decomposes into calcium oxide and carbon dioxide is a decomposition and endothermic reaction, which absorbs 177.8 kJ of energy.
Step-by-step explanation:
The reaction in question is CaCO3(s) + energy → CaO(s) + CO2(g). This reaction is an example of a decomposition reaction because a single compound, calcium carbonate (CaCO3), is breaking down into two simpler products, calcium oxide (CaO) and carbon dioxide (CO2). In addition, the reaction is also endothermic, as it absorbs 177.8 kJ of heat from the surroundings, which is indicated by the positive heat of reaction and by the fact that energy is written on the reactant side in the thermochemical equation.