Do the number of atoms change in a chemical reaction? i will give brainliest

No.

Explanation:

The reason comes the Law of Conservation of Mass.

In an ordinary chemical reaction, you cannot create or destroy atoms.

So, you must have as many atoms at the beginning of a reaction (in the reactants) as at the end (in the products)

We use this principle to balance chemical equations.

For example, the equation for the formation of water from hydrogen and oxygen is

2H₂ + O₂ ⟶ 2H₂O

There are four atoms of H and two of O both before and after the reaction.

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.