Entire explanation with equations: 5 Marks
Effect of heat on metal carbonates : The carbonates of highly reactive metals like Na, K etc. which lie near the top of activity series are stable to heat.
The carbonates of Ca, Mg, Al etc., decompose on heating to give metal oxide and carbon dioxide.
MgCO3Δ−→MgO+CO2
CaCO3Δ−→CaO+CO2
The carbonates of Zn, Cu also decompose on heating to give metal oxide and carbon dioxide.
ZnCO3Δ−→ZnO+CO2
CuCO3Δ−→CuO+CO2
The metal carbonates lying near the bottom of series decompose on heating, giving metal, oxygen and carbon dioxide. For example
2Ag2CO3Δ−→4Ag+O2+2CO2