Can you guys me. fill in the blank 1. a(n) chemical is a description of a reaction using element symbols and chemical formulas. 2.. are the starting substances in a chemical reaction. 3.. are the substances produced by a chemical reaction. 4. mass is conserved in a chemical reaction because atoms are not or 5.to show that mass is conserved, a chemical equation must be which means that the number of each type of atoms must be the same on both sides of the equation. 6. numbers in front of the symbols and formulas in an equation are called study the following equation, then answer questions on the lines provided. al (s) + cucl (aq) → alcl3 (aq) + cu (s) 7. what are the products? 8. what are the reactants?