Question

reactants are the substances going into a chemical reaction. products are the result of the reaction. both reactants and products are substances. what type of substance is reactant b? a nucleus an element a compound a mixture

Explanation:

An element is made of only one - type of atom. Reactant B consists of molecules with two identical atoms bonded together, which is the characteristic of an element. A nucleus is the central part of an atom, a compound has different types of atoms bonded, and a mixture is a combination of different substances not chemically combined.

Answer:

B. An element