According to the law of conservation of matter, which statement about chemical reactions is true? A. Atoms cannot be created or destroyed by chemical reactions. B. Atoms are created by some reactions and destroyed by others. C. Energy is created as atoms are destroyed in chemical reactions. D. Every atom destroyed in a chemical reaction must be replaced.

The equation below shows the reaction of zinc with hydrochloric acid (hcl). zn (s) + 2 hcl (aq) —> zncl2 (aq) + h2 (g) what will happen if the concentration of hcl is decreased? a. more zncl2 will be produced. b. the reaction rate will slow down. c. the hydrochloric acid will become more acidic. d. the reaction will produce water instead of hydrogen gas.