Combination reactions can take place between two elements or between two element and compound or between two compounds.
During chemical reaction, the reactants are the substances that react during a chemical reaction, while the products are the substances that are produced during a chemical reaction.
Combination reaction is defined as the reaction in which two or more reactants combine to form a single product is known as a combination reaction. The general reaction equation for combination reaction is,
A + B → AB
2Na + Cl2 → 2NaCl