text: stp chemisty question? aluminum metal shavings (10.0g) are placed in 100. ml of 6.00 m of hydrochloric acid. what is the maximum volume of hydrogen, measured at stp, which can be produced?  2al(s) + 6hcl(aq) yields 2alcl3(aq) + 3h2(g) find the moles of al:  n = m/ar = 10/27 = 0.37 mol (approx) where ar = 27 is the relative atomic mass of al.  find the moles of hcl:  n = c*v = 6*0.1 = 0.6 mol hcl  according to the balanced chem. equation:  2al + 6hcl  --> 2alcl3 + 3h2  1 mol of al reacts with 3 mol of hcl, so 0.37 mol of al reacts with 3*0.37 = 1.11 mol of hcl  so hcl is the limiting reactant and because:  6 mol of hcl produces 3 mol h2 0.6 mol of hcl produces 0.3 mol h2  this quantity - 0.3 mol of h2 - at stp occupies:  v = n*vm = 0.3*22.4 = 6.72 l, where vm = 22.4 l/mol is the molar volume in stp.