how much grams of cao is produced by oxidation of 1gm of calcium

2Ca + O2 ==> 2CaO

mols Ca = grams/atomic mass = ?
Use the coefficients in the balanced equation to convert mols Ca to mols CaO. In this case mols Ca = mols CaO
Then convert mols CaO to grams. g = mols CaO x molar mass CaO.