first, write out the complete reaction scheme for this process.
Then calculate the number of moles of CaCO3 based on the molar mass and the given mass.
Then based on the reaction scheme, you know how many moles CaO is produced
Then calculate the mass of CaO based on the number of moles produced and the molar mass of CaO
the question is not very clear, bu i think it is meant that you have to divide 13,1 by the amount found in question a) and then multiply by 100. Then you have the percentage yield
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