How many moles of caco3 would have to be decomposed to produce 129 grams of cao?

2.3 moles CaCO₃

That is;

CaCO₃(s) → CaO(s) +CO₂(g)

From the question, 129 grams of CaO were formed

We are required to calculate the number of moles of CaO used.

This can be done in the following steps;

Step 1: Moles of CaO produced

The number of moles is calculated by dividing mass by the molar mass of a compound.

Molar mass of CaO is 56.0774 g/mol

Therefore;

Moles of CaO = 129 g ÷ 56.0774 g/mol

                       = 2.3 moles

Step 2: Moles of CaCO₃ decomposed

From the equation 1 mole of CaCO₃ decomposes to yield 1 mole of CaO

Therefore;

For 2.3 moles of CaO to be produced then 2.3 moles of CaCO₃ would be decomposed.

Therefore;

The moles of CaCO₃ decomposed is 2.3 moles