Question

Calculate the moles of calcium chloride (CaCl2) needed to react in order to produce 85.00 grams of calcium carbonate (CaCO3).

Answer 1

The reaction between the mentioned substances can be shown as following:

CaCl₂ + Na₂CO₃ = 2NaCl + CaCO₃

First, the mass of CaCO₃ should be converted into moles:

n = m/Mr

where n - number of moles, m - mass, Mr - molecular weight

n(CaCO₃) = m(CaCO₃) / Mr(CaCO₃) = 85.00 g /100.09 g/mol = 0.85 mol

As can be seen from the reaction, 1 mole of CaCl₂ reacts to produced 1 mole of CaCO₃. As a result, 0.85 mole of CaCl₂ will also react to produce 0.85 mole or 85.00 g of CaCO₃.

Answer: 0.85 mol