Question

The reaction between hydrochloric acid and aluminum produces hydrogen gas and aluminum chloride. The balanced reaction equation is given below. How many motes of H_2 can be obtained when 7.80 mol HCl reacts with an excess of Al? 6HCl + 2Al rightarrow 3H_2 + 2AlCl_3

Answer 1

Answer – We are given moles of HCl = 7.80 moles

Reaction - 6 HCl + 2 Al ------> 3 H_­2 + 2 AlCl₃

We are given that HCl is limiting reactant and Al is excess, so for the given data and from the balanced reaction –

6 moles of HCl = 3 moles of H₂

So, 7.80 moles HCl = ?

= 7.80 moles HCl * 3 moles of H₂ / 6 moles of HCl

= 3.90 moles of H₂

So, 3.90 moles of H₂ can be obtained.