Which ions aren't shown in net ionic reactions, because they are present as both reactants and products of the reaction, so they do not participate in the reaction?

Explanation:

This is correct!

Ions that exist in both the reactant and product side of the equation are referred to as spectator ions. Overall, they do not partake in the reaction. If they are present on both sides of the equation, you can cancel them out.

An example is;

Na+(aq) + Cl−(aq) + Ag+(aq) + NO3−(aq) → Na+(aq) + NO3−(aq) + AgCl(s)

The ions; Na+, NO3−(aq) would be cancelled out to give;

Cl−(aq) + Ag+(aq)  → AgCl(s)

answer: c.

explanation:

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.