Chemical Reactions

What is a chemical reaction?

• a change in matter when the molecules rearrange to make new molecules

• a change in matter when matter changes its form or appearance

• a change in matter when the physical appearance changes

• a very boring change in matter

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

This change is a

• chemical reaction

• physical change

• musical change

• all answers are correct

Tags

NGSS.MS-PS1-4

Which of the following is an example of a physical change?

• Melting of ice

• Burning of wood

• Rusting of iron

• Cooking an egg

What is the main difference between a chemical change and a physical change?

• Chemical change involves a change in state, while physical change does not.

• Chemical change results in new substances, while physical change does not.

• Physical change involves energy absorption, while chemical change does not.

• Physical change is irreversible, while chemical change is reversible.

Which of the following indicates a chemical reaction has occurred?

• Change in color

• Change in temperature

• Formation of a precipitate

• All of the above

Tags

NGSS.MS-PS1-2

Which of the following is a sign of a physical change?

• Change in color

• Formation of a gas

• Change in shape

• Production of heat

What happens to the molecules during a chemical change?

• They rearrange to form new substances

• They remain unchanged

• They become larger

• They disappear

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is NOT a chemical change?

• Burning of paper

• Rusting of a nail

• Boiling of water

• Cooking of food

Tags

NGSS.MS-PS1-2