The balanced chemical equation for the reaction of sodium (Na) and chlorine gas (Cl₂) to form sodium chloride (NaCl) is:

2 Na + Cl₂ → 2 NaCl

Here's the breakdown of the coefficients:

* 2 Na: This means that two atoms of sodium are required for the reaction.

* 1 Cl₂: This means that one molecule of chlorine gas is required for the reaction.

* 2 NaCl: This means that two molecules of sodium chloride are produced as a result of the reaction.

Coefficients in a chemical equation represent the number of moles of each reactant and product involved in the reaction. They ensure that the number of atoms of each element is the same on both sides of the equation, adhering to the law of conservation of mass.