Question

What happens to atoms during a chemical reaction?

Answer 1

Hint: In a chemical reaction, the nucleus of an atom is not affected. The electrons present in the valence shell take part in a chemical reaction.

Complete step by step answer:
In a chemical reaction, one or more bonds of reactant(s) breaks and few new bond forms. These new bonds along with the unaffected bonds define the product(s).
The nuclei of atoms remain the same. We know that a bond is formed by transferring or sharing electrons. By rearrangement of electrons, a bond between two atoms breaks and a new bond forms between one of the atoms and a new atom.
We know that an element is defined by its atomic number or the number of protons in its nucleus. Therefore, transferring and sharing of electrons will not affect the identity of that element.
Hence, during a chemical reaction, an atom may gain or lose electrons but the nucleus of the atom remains unaffected.

Note: The total numbers of atoms of each element remain the same in products as they were in reactants. A chemical reaction occurs when the following two conditions are met:
Reactants can arrange themselves to a more favourable state in products.
There must be energy available for them to initiate this change.
When there is energy available to break the chemical bonds of reactants, then the reactants convert to products. The product is in a low energy state, which means it is in a more stable form. Now the formation of chemical bonds of products releases energy which is used to break more bonds of reactants. The above process creates chain reactions and all the molecules which can react, do react.