How many copies of h2 are required to balance this chemical equation? 2al + 6hcl __h2 + 2alcl3

Balancing the equation will require 3 copies of H2

Explanation:

The chemical equation is as follows ;

2Al + 6HCl→H2 + 2AlCl3

From the equation Aluminium reacts with Hydrogen chloride to produce hydrogen and Aluminium chloride .

A chemical equation is composed of a reactant side and a product side. The number of atom of element on both side needs to be equal for an equation to be balanced.

On the reactant sides, we have 2 atom of aluminium and 6 atom of hydrogen and 6 atom of chlorine in hydrogen chloride molecules.

On the product sides, we have 2 atom of hydrogen and 2 atom of Al and 6 atom of chlorine in the aluminium chloride compound. The number of atom of H2 is short on the product side . so, balancing it will require adding the coefficient 3 to it, to make it 6 atoms of hydrogen on the product side.

So balancing the equation will require 3 copies of H2 to balance the equation. Balanced equation is  

2Al + 6HCl → 3H2 + 2AlCl3