Stoichiometry questions

Question

H₃PO_{4(aq) +} MgCO_3(aq) —> Mg₃(PO₄)_2(s) + CO_2(g) + H₂O(l)

if 60 grams of hydrogen phosphate react with 60.0 grams of magnesium carbonate, how many grams of carbon dioxide can be found?

Answer 1

2H₃PO_{4(aq) +} 3MgCO_3(aq) —> Mg₃(PO₄)_2(s) + 3CO_2(g) + 3H₂O(l) ... balanced equation

Now that we have a correctly balanced equation, we can use dimensional analysis to solve the problem by first finding the limiting reactant, and then the final answer.

For H₃PO₄: 60 g H₃PO₄ x 1 mole/97.99 g x 3 mol CO₂/2 mole H₃PO₄ x 44 g CO₂/mol = 40.4 g CO₂

For MgCO₃: 60 g MgCO₃ x 1 mole/84.31 g x 3 mol CO₂/3 mol MgCO₃ x 44 g CO₂/mol = 31.3 g CO₂

Since MgCO₃ is limiting, it will dictate the amount of CO₂ that can be produced. So, the answer would be

31.3 g of CO₂