Na₂CO₃(s) + 2HCl --> 2NaCl(aq) + H₂O (l) + CO₂. You start counting carbon atoms and make the adjusments so you have the same amount of atoms at both sides of the equation then repeat with Na, Cl, H and last O atoms.
2.16. From ther balanced equation you can observed that for each 2 moles of HCl consumed in the reaction, 1 mol of CO₂ is produced. So when 4.32 moles of HCl are consumed 2.16 moles of CO₂ are produced
