The chemical equation of the reaction between aluminum and acetic acid.
If aluminum is a metal, it is active. If acetic acid is a weak acid, it will react when the two meet.

Aluminum ($Al $) has the general property of metals and is prone to lose electrons when exposed to acid. Although acetic acid ($CH_3COOH $) is a weak acid, it also contains ionizable hydrogen ions.

At the beginning of the reaction, the outer electrons of aluminum atoms are attracted by hydrogen ions in acetic acid, and aluminum loses electrons and forms aluminum ions ($^ Al {3 + }$）， hydrogen ions get electrons and form hydrogen ($H_2 $). Acetate ions ($CH_3COO ^ - $) combine with aluminum ions.

The initial reaction formula can be expressed as: $Al + CH_3COOH\ longrightarrow Al (CH_3COO) _x + H_2 ↑ $.

To balance this formula, according to the principle of conservation of charge and atom. Aluminum ions are $+ 3 $valence, acetate ions are $- 1 $valence, so $x = 3 $, that is, $Al (CH_3COO) _3 $.

In addition, due to the conservation of hydrogen atoms, hydrogen atoms in acetic acid generate hydrogen, and 2 dollars of acetic acid molecules provide 2 dollars of hydrogen ions to generate 1 dollar of hydrogen molecules. 3 dollars $acetate ions require 3 dollars $acetic acid molecules, so the pre-acetic acid coefficient is 6 dollars $.

After balancing, the chemical equation of equilibrium is obtained: $2Al + 6CH_3COOH = 2Al (CH_3COO) _3 + 3H_2 ↑ $.

This balancing formula accurately presents the proportional relationship between aluminum and acetic acid reaction, which is an important guide for chemical research and experimental operation.