15. An equation that gives the names of the substances involved in a reaction.
Word equation
Explanation for correct option:
(B) Word equation:
This would represent a word equation.
Explanation for incorrect options:
(A) Chemical equation:
A symbolic representation of the changes which occur in a chemical reaction, expressed in terms of the formulae of the molecules involved, is called a chemical equation. For example,
The balanced chemical equation of water is
(C) Chemical formula:
A set of chemical symbols showing the elements present in a compound and their relative properties is called a chemical formula. For example, the chemical formula for water is.
(D) Chemical symbol:
The letters used to represent elements are called chemical symbols. For example, the symbol of Boron is .
So the correct answer is an option (B).