Introduction to Chemical Reactions Answers

Which is an example of a chemical reaction?

Reggie and Charlotte are baking oatmeal cookies. They dip the baked cookies in melted chocolate. The chocolate cools to form a hardened coating. Reggie argues the entire chocolate-covered cookie has undergone a chemical change. Charlotte disagrees, saying only the original oatmeal cookie has undergone a chemical change, not the chocolate coating.

Two chemicals react in an endothermic reaction. What can be known about this reaction?

Which best explains why a firework being ignited is an example of an exothermic reaction and not an endothermic reaction?

When liquid silver nitrate and liquid sodium chloride are combined, solid silver chloride forms along with a new liquid, sodium nitrate. Which substance represents the precipitate?

Theresa creates an experiment where she mixes two red-colored substances together in a container and observes the solution slowly changing from red to blue for the next eight minutes. The solution becomes completely blue after eight minutes.

Which of these most likely represents a chemical change?

What must occur in order for a chemical reaction to be specifically classified as endothermic instead of exothermic?

When vinegar and baking soda react, the mixture becomes cold to the touch and a gas and a new liquid substance are formed.

For a science project, Janet performs four experiments that are supposed to show a chemical reaction. She displays her results in a table.