How to write a balanced equation?

Question

for this chemical reaction
Aluminum reacts with aqueous hydrochloric acid to form hydrogen gas and aqueous aluminum chloride.

Answer 1

For any equation, start with the correct chemical formulas of all substances. Al + HCl = H2 + AlCl3. You need two H's and three Cl's to balance, so go for a LCM of 6 for the HCl. That will give you three H2's, and two AlCl3's - and for that you need 2 Al's. So the equation will read 2Al + 6HCl = 3H2 + 2AlCl3. OK?

Answer 2

Al + HCl -----> H2 + AlCl

On the left we have:
1 mole Al
1 mole H
1 mole Cl

On the right we have:
1 mole Al
2 moles H
1 mole Cl

To balance this equation, a 2 can be placed in front of the HCl on the left.

Al + 2HCl -----> H2 + AlCl

On the left:
1 Al
2 H
2 Cl
On the right:
1 Al
2 H
1 Cl

To fix this:

Al + 2HCl -----> H2 + 2AlCl

On the left:
1 Al
2 H
2 Cl
On the right:
2 Al
2 H
2 Cl

To fix this...

2Al + 2HCl -----> H2 + 2AlCl

Now everything is balanced. Two moles of each element on either side.

Answer 3

AL +HCL=H + ALCL

Answer 4

2Al + 6HCl -----> 2AlCl3 + 3H2