Physical & Chemical Changes

Metals are useful materials in that they are good conductors of heat and electricity. Metals that can be changed to meet specific needs. All of the following changes to a metal are physical changes except -

• bending

• melting

• rusting

• polishing

An older bicycle shows wear and tear. Which of the following signs show that a chemical change has occurred to the bicycle?

• rust on the wheel

• broken light

• torn seat cover

• bent handle bar

Tags

NGSS.MS-PS1-2

In the laboratory, a blue liquid is mixed with a yellow liquid. What would be the best evidence that a chemical change took place as the liquids were mixed?

• The new liquid is green.

• The yellow liquid floats on top of the blue.

• The formation of a gas.

• No change in the temperature of the new solution.

Tags

NGSS.MS-PS1-2

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

• grinding salt crystals to a powder

• the evaporation of water from a mud puddle

• ice melting in a glass

• burning wood in a campfire

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

All of the following are evidences of a chemical change except -

• a change in temperature

• the production of a gas

• a change in state of matter

• an odor being given off

Tags

NGSS.MS-PS1-2

Every chemical change results in -

• a change in temperature.

• the formation of a new substance.

• a color change.

• the formation of a precipitate.

Tags

NGSS.MS-PS1-2

The precipitate formed in the reaction is evidence of a chemical change because -

• a new substance has been formed.

• a change in the state of matter has occurred.

• a color change has taken place.

• a change in temperature has taken place.

Tags

NGSS.MS-PS1-2

During digestion the body uses both physical and chemical changes to move and process food. Which of the following is an example of a physical change?

• Teeth breaking food down into smaller pieces.

• Protein breaking down into amino acids in the stomach.

• Enzymes breaking down carbohydrates into simple sugars.

• Hydrochloric acid breaking down fats in the stomach.

Evidence of a chemical change can be observed when -

• a solid melts into a liquid.

• cookies are crumbled.

• a drink is poured from a can to a cup.

• a banana turns brown after being cut.

Tags

NGSS.MS-PS1-2

Which of the following is NOT evidence of a chemical change?

• the temperature changes

• a gas forms

• a precipitate forms

• a state of matter change happens

Tags

NGSS.MS-PS1-2