Me with a couple of ! you : ) 1. what is a chemical reaction? a. any time a substance is mixed with another substance b. any time different substances combine to form a new substance, or when a substance breaks up into different substances c. any time a substance is heated, frozen, or evaporated 2. balancing chemical equations is called: a. stoichiometry b. chemolibrium c. equivalentry 3. sulfuric acid is made of two hydrogen atoms (h), one sulfur atom (5), and four oxygen atoms (0). what is its formula? a. 2h4s0 b. h4s20 c. h2s04