Introduction to Chemical Reactions Answers

Which best describes what happens to the atoms in a chemical reaction?

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

Which is an example of a chemical reaction?

When baking soda and vinegar react, the surface bubbles. What does this most likely indicate?

Cherylanne mixes together Chemical A and Chemical B in a test tube, forming Chemical C. The mixture instantly turns cool to the touch. She then adds Chemical D, and the reaction becomes hot and explodes.

Which is evidence that a chemical reaction has likely occurred?

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.

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?

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

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

A Venn diagram is used to compare and contrast different topics. The items that are unique to each topic are represented in the separate sections of the circles, and the items that are common to both topics are represented in the center overlapping sections. Harlow creates this Venn diagram comparing and contrasting endothermic and exothermic processes.

Which of these most likely represents a chemical change?