Phase Change Lesson

Which phase represents molecules with the greatest freedom of movement?

• Solid

• Plasma

• Liquid

• Gas

What is the phase change when a substance changes from liquid to gas?

• Evaporation

• Melting

• Condensation

• Freezing

Tags

NGSS.MS-PS1-4

What is the phase change when a substance changes from liquid to solid?

• Freezing

• Condensation

• Melting

• Evaporation

Tags

NGSS.MS-PS1-4

What will you write an explanation for in Activity 5?

• The models showing vaporization and solidification

• The models showing sublimation and deposition

• The models showing condensation and melting

• The models showing evaporation and freezing

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

A student left a sealed jar of water outside her home. Water can be a solid, liquid, or gas. When she put it outside, the water was a solid. Twelve hours later, the water had changed phase and was a liquid. What happened to the water molecules?

• Before the student left, the molecules were moving in place. After, the molecules were moving around each other.

• Before the student left, the molecules were moving around each other. After, the molecules were moving away from each other.

• Before the student left, the molecules were moving around each other. After, the molecules were moving in place.

• Before the student left, the molecules were moving away from each other. After, the molecules were moving around each other.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Lily is doing a science experiment with a substance in a sealed jar. At first, the substance’s molecules are moving around each other. What will happen to Lily’s substance if she transfers energy into the substance and causes a phase change?

After the phase change, the substance’s molecules will move . . .

• faster, and the substance will be a liquid.

• faster, and the substance will be a gas.

• slower, and the substance will be a solid.

• slower, and the substance will be a liquid.

Tags

NGSS.MS-PS1-4

A scientist has a container with a substance inside. At first, the molecules in the substance move away from each other. Later, the molecules move around each other. What change did the scientist observe in the substance?

• Before, the substance was a liquid. Later, it was a solid.

• Before, the substance was a gas. Later, it was a liquid.

• Before, the substance was a liquid. Later, it was a gas.

• Before, the substance was a solid. Later, it was a liquid.

Tags

NGSS.MS-PS1-4

A cook had a jar containing a sweet food and a jar containing a sour food. The image above shows the sweet and sour foods. At room temperature, both foods are liquids. The same amount of energy was transferred into both substances. Later, one of the foods had changed phase while the other had not. Which food changed phase, and how did it change?

• The sweet food changed because the molecules were able to move fast enough to overcome the attraction between them. Its molecules now move away from each other.

• The sweet food changed because the strong attraction between molecules made their movement slower. Its molecules now move around each other.

• The sour food changed because the weak attraction between molecules let them move faster. Its molecules now move away from each other.

• The sour food changed because the molecules were able to move fast enough to overcome the attraction between them. Its molecules now move in place.

Tags

NGSS.MS-PS1-4

Mario is making chocolate. In part of the chocolate-making process, he changed the phase from a liquid to a solid. What happened to the molecules of chocolate when it changed phase?

• Before changing phase, the molecules were moving around each other. After changing phase, they were moving away from each other.

• Before changing phase, the molecules were moving around each other. After changing phase, they were moving in place.

• Before changing phase, the molecules were moving away from each other. After changing phase, they were moving around each other.

• Before changing phase, the molecules were moving in place. After changing phase, they were moving around each other.

Tags

NGSS.MS-PS1-4

A scientist has two substances that she is testing in her lab: a pink substance and a green substance. At room temperature, both substances are liquids. The scientist transferred the same amount of energy into both substances. She finds only the pink substance changed phase. How is the pink substance different from the green substance?

The pink substance has a . . .

• weaker attraction between its molecules than the green substance. Its molecules now move away from each other.

• weaker attraction between its molecules than the green substance. Its molecules now move in place.

• stronger attraction between its molecules than the green substance. Its molecules now move away from each other.

• stronger attraction between its molecules than the green substance. Its molecules move around each other.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4