Question

balance this equation _ai +_hci → _h₂ +_aici3 4, 12, 3, 4 2, 1, 4, 5 2, 6, 3, 2 it is already balanced

Explanation:

Step1: Balance the equation

The unbalanced equation is \( \text{Al}+\text{HCl}
ightarrow\text{H}_2+\text{AlCl}_3 \).
First, balance the chlorine atoms. There are 3 chlorine atoms in \( \text{AlCl}_3 \) and 1 in \( \text{HCl} \). So, multiply \( \text{HCl} \) by 6 to get 6 chlorine atoms on the left - hand side.
The equation becomes \( \text{Al}+6\text{HCl}
ightarrow\text{H}_2+\text{AlCl}_3 \).
Now, balance the hydrogen atoms. There are 6 hydrogen atoms in \( 6\text{HCl} \). So, multiply \( \text{H}_2 \) by 3 to get 6 hydrogen atoms on the right - hand side.
The equation is \( \text{Al}+6\text{HCl}
ightarrow3\text{H}_2+\text{AlCl}_3 \).
Finally, balance the aluminium atoms. There is 1 aluminium atom on the left - hand side and 1 in \( \text{AlCl}_3 \). Multiply \( \text{Al} \) by 2 and \( \text{AlCl}_3 \) by 2 to get 2 aluminium atoms on both sides.
The balanced equation is \( 2\text{Al}+6\text{HCl}
ightarrow3\text{H}_2 + 2\text{AlCl}_3 \).

Answer:

2, 6, 3, 2