Ans: Calcium oxide has different physical properties and different chemical properties.
Physical properties are measurable properties that describe the state of a physical system. These include: density, melting point, boiling point, colour (appearance) etc.
Chemical properties describe the composition of matter and therefore, its ability to undergo chemical change. For example: heat of combustion, enthalpy of formation, oxidation state, reactivity of that element/compound are all chemical properties.
In the given example: calcium carbonate decomposes to form calcium oxide and carbon dioxide.
[tex]CaCO_{3} (s)[/tex]→[tex]CaO(s) + CO_{2} (g)[/tex]
Although both Calcium oxide and calcium carbonate are white solids, they have different densities as well as different melting and boiling points. Therefore, they have different physical properties.
Calcium oxide is composed of 1 Ca and 1 O atm whereas, calcium carbonate has 1 Ca, 1 C and 3 O atoms. The two differ in their chemical composition, hence have different chemical properties.
