Question

define chemical reaction and equations?

Answer 1

Chemical reaction. Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. ... A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and formulae, wherein the reactant entities are given on the left-hand side and the product entities on the right-hand side.
2 HCl + 2 Na → 2 NaCl + H2
hope this is the answer you are looking for

Answer 2

When 2 or more chemicals (substances) react with each other to form a new substance is called a chemical reaction.
chemicals reacting are called reactants.
new substances form is called product.
To show a chemical reaction we form a chemical equation.