1.1 and 1.2

Question 1

Chemical Reactions

Answer 1

a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction.

Question 2

exothermic

Answer 2

accompanied by the release of heat.

Question 3

precipitate

Answer 3

cause (an event or situation, typically one that is undesirable) to happen suddenly, unexpectedly, or prematurely.