Question

What is the total number of moles of carbon dioxide formed on thermal decomposition of 4 moles of limestone

Answer 1

Limestone refers to crystals of calcium. It can either be calcite (calcium carbonate, CaCO3) or dolomite (CaMg(CO3)2). The thermal decomposition of them is as follows:

Calcite: CaCO3 → CaO + CO2

Dolomite: CaMg(CO3)2 → CaO + MgO + 2 CO2

As reactions shows, calcite on thermal decomposition will lead to the formation of 4 moles of CO2 and 4 moles of dolomite will lead to the formation of 8 moles of CO2 .