91Ó°ÊÓ

To start, we need to write down the formulas of the reactants involved in the reaction. We are given that aluminum metal (\(Al\)) reacts with concentrated aqueous sodium hydroxide (\(NaOH\)). So, our reactants are \(Al\) and \(NaOH\).

This reaction is a single displacement reaction, where aluminum displaces another element from its compound. In this case, aluminum will displace hydrogen from sodium hydroxide to form aluminum hydroxide and hydrogen gas. The general formula for the reaction is: \[Al + NaOH \rightarrow Al(OH)_3 + H_2\]

To balance the chemical equation, we need to make sure that the number of atoms of each element is the same on both sides of the equation. 1. Aluminum: There is one aluminum atom on the reactant side and one aluminum atom in the product side, so it is already balanced. 2. Sodium: There is one sodium atom on the reactant side and none in the product side. We need 3 sodium atoms to form aluminum hydroxide, so we multiply sodium hydroxide by 3. 3. Hydrogen: There are three hydrogen atoms in aluminum hydroxide and one hydrogen atom in sodium hydroxide, so we have a total of 3 + 1 = 4 hydrogen atoms on the product side. Hydrogen gas has two hydrogen atoms, so we multiply it by 2. 4. Oxygen: There are three oxygen atoms in aluminum hydroxide and one oxygen atom in sodium hydroxide, so we have a total of 3 + 1 = 4 oxygen atoms on the product side. We don't need to do anything for oxygen, since it is already balanced. Balanced chemical equation: \[2Al + 6NaOH \rightarrow 2Al(OH)_3 + 3H_2\]