Chemical vs Physical Changes

Which of these four liquids is a mixture, made of parts, some of which can be separated?

• salt water

• skim milk

• orange juice

• distilled water (drinking water)

Which is a physical change?

• burning wood

• rusty nail

• freezing water

• baking cookies

Which is a chemical change?

• rusted bike

• cutting an apple

• boiling water

• tearing paper

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is the best way to separate a mixture of sugar, sand, and water?

• Freeze the mixture, causing the water to be destroyed, then sift the sugar from the sand.

• Filter the sand from the sugar and water, then heat the mixture, causing the water to evaporate.

• Filter the mixture, causing the sugar and sand to get caught but not the water.

• Stir the mixture, causing the water to move above the sugar and sand.

A student is investigating changes with common classroom materials. Which of the following BEST describes the conclusion the student can make about the investigations?

• The paperclip shows evidence of a physical change by changing the shape of the object, whereas the pencil eraser and hole puncher show evidence of a physical change by changing the size of the object.

• All three investigations show evidence of a physical change due to a change in the color of the original substance.

• The paperclip and hole puncher shows evidence of a physical change by changing the chemical properties of the original object, whereas the pencil eraser shows evidence of a physical change by changing the size of the object.

• All three investigations show evidence of a physical change due to a change in state of matter.

A 5th grade student places baking soda in a cup. The student then adds vinegar to the cup. The student collects the data below from the experiment. Based upon the results of the experiment, which statement BEST describes whether the change is a physical or chemical change.

• The data concludes that a physical change has occurred because it had an increased change in temperature, which resulted in the liquid to start bubbling.

• The data concludes that a physical change has occurred because the color of the liquid changed when you mixed two materials.

• The data concludes that a chemical change has occurred because there was formation of bubbles when the materials reacted to each other.

• The data concludes that a chemical change has occurred because mixing two substances together will always result in a reaction.

Tags

NGSS.MS-PS1-2

A 5th grade student places baking soda in a cup. The student then adds vinegar to the cup. The student collects the data below from the experiment. Based upon the results of the experiment, which statement BEST describes whether the change is a physical or chemical change.

• The data concludes that a physical change has occurred because it had an increased change in temperature, which resulted in the liquid to start bubbling.

• The data concludes that a physical change has occurred because the color of the liquid changed when you mixed two materials.

• The data concludes that a chemical change has occurred because there was formation of bubbles when the materials reacted to each other.

• The data concludes that a chemical change has occurred because mixing two substances together will always result in a reaction.

Tags

NGSS.MS-PS1-2

A teacher takes a tray of ice cubes out of the freezer. Each student takes an ice cube and holds it in their hands. They make the observations listed in the chart. The student claims that changing the temperature of the water causes a physical change that turns water into ice.

Which argument BEST supports the student’s claim?

• The ice cube is melting in the student’s hand since the hands are much warmer than the ice. Heat is being added to the ice, which causes the particles to move faster.

• The ice cube is freezing in the student’s hand since the hands are much warmer than the ice. Heat is being removed from the ice, which causes the particles to move slower.

• The ice cube is melting in the student’s hand since state is changing from a solid to a liquid. Heat is being removed from the ice, which causes the particles to move faster.

• The ice cube is melting in the student’s hand since state is changing from a liquid to a solid. Heat is being added to the ice, which causes the particles to move slower.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

A mixture of sand and gravel can be separated by putting it in a container with holes that only the sand can pass through. This method works to separate the mixture because sand and gravel differ in which physical property?

• texture

• state of matter

• color

• size

Which of the following is NOT a clue that a chemical change has occurred? 

• change of state of matter
• color change
• production of a gas
• production of heat

Tags

NGSS.MS-PS1-2