The thermal decomposition of calcium carbonate CaCO3 produces calcium oxide CaO and carbon dioxide CO2 . The balanced chemical equation for this reaction is:CaCO3 s CaO s + CO2 g To calculate the mass of CaO produced from 5.0 g of CaCO3, we need to use stoichiometry. First, we need to find the molar mass of CaCO3 and CaO.Molar mass of CaCO3 = 40.08 Ca + 12.01 C + 3 * 16.00 O = 100.09 g/molMolar mass of CaO = 40.08 Ca + 16.00 O = 56.08 g/molNow, we can use the balanced equation to find the stoichiometric ratio between CaCO3 and CaO, which is 1:1. Next, we need to convert the mass of CaCO3 to moles:moles of CaCO3 = mass of CaCO3 / molar mass of CaCO3moles of CaCO3 = 5.0 g / 100.09 g/mol = 0.0499 molSince the stoichiometric ratio between CaCO3 and CaO is 1:1, the moles of CaO produced will be equal to the moles of CaCO3:moles of CaO = 0.0499 molNow, we can convert the moles of CaO to mass:mass of CaO = moles of CaO * molar mass of CaOmass of CaO = 0.0499 mol * 56.08 g/mol = 2.80 gSo, 2.80 g of CaO will be produced from the thermal decomposition of 5.0 g of CaCO3.