The reaction between hydrochloric acid and aluminum produces hydrogen gas and aluminum chloride. the balanced reaction equation is given below. how many moles of h2 can be obtained when 3.40 mol hcl reacts with an excess of al?

              3.4 moles of H₂

The Balance Chemical Equation is as follow,

                                   2 Al + 6 HCl     →    3 H₂ + 2 AlCl₃

Calculating moles of H₂ produced,

According to equation,

                          3.0 moles of HCl produces  =  3.0 moles of H₂

So,

                 3.40 moles of HCl will produce  =  X moles of H₂

Solving for X,

                      X  =  (3.40 mol × 3.0 mol) ÷ 3 mol

                      X  =  3.4 moles of H₂

i just got this problem. it's 90.3