we can determine that 2 moles of HClHCl will react with 2 moles of Na(s)Na(s) to form 2 moles of NaCl(aq)NaCl(aq) and 1 mole of H2(g)H2(g). If we know how many moles of NaNa we start out with, we can use the ratio of 2 moles of NaClNaCl to 2 moles of Na to determine how many moles of NaClNaClwere produced or we can use the ration of 1 mole of H2H2 to 2 moles of NaNa to convert to NaClNaCl. This is known as the coefficient factor. The balanced equation makes it possible to convert information about one reactant or product to quantitative data about another element. Understanding this is essential to solving stoichiometric problems.