Grade

In a chemical reaction, sulfuric acid and aluminium metal react

to form hydrogen gas and a salt solution of aluminium sulfate.

Ben has written this equation for the reaction:

Al + H, SO (g) → A1, (SO) 3 (aq) + H, (R

Ben's equation is not balanced. Write a balanced chemical equation for this reaction.

2Al + 3H2SO4 (g) → Al2 (SO4) 3 (aq) + 3H2 (g)

Explanation:

On the right side we have Al2 (so 2x aluminium, So on the left side we multiply Al by 2, On both sides is 2x Al now)

The formula for Sulfuric acid is H2SO4.

The result (aluminium sulfate) is Al2 (SO4) 3. Aluminium has an oxidation number of + 3, SO4 has an oxidation number of - 2 (S (+6) + 4O (4x-2) : 6-8 = - 2

So we have to multipy aluminium 2x and SO4 (3x) to equal.

On the right side we have 3x S, so on the right side we have to multiply H2SO4 also by 3 to get the same amount.

This results in 12x Oxygen (3xO4). Which is the same as the right side.

On the left side we have 6H (3xH2) so on the right side we multiply H2 by 3 to get the same amount.

So we have on both sides:

2x Al

6xH

3xS

12xO