Question

A 0.75 g sample of X2CO3 is dissolved in water and 80 mL of 0.20 M CaCl2 solution is added.
This is the balanced equation I have created.
X2CO3(aq) + CaCl2(aq) → CaCO3(s) + 2 XCl(aq)

Based on the ratio in your balanced equation, how many moles of X2CO3 must have reacted? How many moles of CO32- is this?

I don't know how to start.

Answer 1

I know that the moles of each compound is the coefficient.

Answer 2

mols CaCl2 = M x L = ?
mols X2CO3 = mols CaCl2 from the 1:1 ratio.
mols (CO3)^2- = mols X2CO3 = mols CaCl2.