Question

How many moles of MgCO3 are in 2.57g of MgCO3?

Answer 1

Answer:

0.0305 moles of MgCO₃

Explanation:

In order to solve this problem, we first need to calculate the molecular weight of MgCO₃:

• MgCO₃ MW = Atomic mass Mg + Atomic mass C + (Atomic mass O)*3

• MgCO₃ MW = 24.3 + 12 + 16*3 = 84.3 g/mol

Finally we divide the mass by the molecular weight, to calculate the number of moles:

• 2.57 g MgCO₃ ÷ 84.3 g/mol = 0.0305 moles.