Unit 6 Review

The melting/freezing point of mercury is -39C. A scientist put liquid mercury into a freezer that is kept at a constant temperature of -35C. Will the liquid mercury freeze?

• The mercury will not freeze because the freezer is warmer than the freezing point of mercury.

• The mercury will freeze because the freezer is warmer than the freezing point of mercury.

• The mercury will not freeze because the freezer is colder than the freezing point of mercury.

• The mercury will freeze because the freezer is colder than the freezing point of mercury.

Tags

NGSS.MS-PS1-4

What is between the water particles in a glass of pure water?

• Cohesive forces

• Adhesive forces

• Nothing but space

• Air

Tags

NGSS.MS-PS2-5

When a substance changes from a liquid to a solid, which of the following is true? Choose 3

• The particles change shape

• The particles are held more strongly to one another.

• The particles have more kinetic energy.

• The particles have less kinetic energy.

• The substance is freezing.

Tags

NGSS.MS-PS1-4

Sugar can melt, and sugar can dissolve. Choose each statement that explains what happens at the particle level when melting or dissolving occurs. Choose 2

• Sugar melts when its particles get soft enough to turn into liquid

• Sugar melts when a liquid breaks particles away from the solid substance

• Sugar melts when kinetic energy increases enough for the particles to move past one another

• Sugar dissolves when a liquid breaks particles away from the solid substance

• Sugar dissolves when its particles get soft enough to turn into liquid

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

You wash a T-shirt. You hang the wet T-shirt on a clothesline. A few hours later, the T-shirt is dry. Choose each statement that explains what happens to the water particles after you hang the shirt up.

• The water particles are

  absorbed by the T-shirt

• The water particles evaporate

  into the air

• The water particles disappear

  and no longer exist

• The water particles disappear

  and no longer exist

• The water particles moved

  faster and become part of the

  air

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Student dissolved 20 g salt in a cup of water. She left the cup uncovered in an area where nobody could touch it. When she returned to the cup 10 days later, she found that all of the water was gone, and there were crystals in the bottom of the cup. What is the best conclusion based on her observation?

• The water evaporated, and there is 20 g if salt in the cup

• The water and some salt evaporated, but some salt is left in the cup

• There was a chemical reaction, and a precipitate was left behind

• The water and salt separated and then the water evaporated, but there s no way to know what is

  left in the cup

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Bridges are often built using expansion joints like the one shown. The reason is because -

• Matter contracts when it gets warmer in the summer, and expands when it gets cooler in the

  winter.

• Matter expands when it gets warmer in the summer, and contracts when it gets cooler in the

  winter.

• When the average kinetic energy increases, it turns a solid into a liquid.

• The average kinetic energy of the air around the road is constantly changing throughout the day.

Which temperature represents absolute zero?

• 0 K

• 0 C

• 273 K

• 273 C

Solid X is placed in contact with solid Y. Heat will flow spontaneously from X to Y when - remember moves from hot to cold

• X is 20^oC and Y is 20^oC

• X is 10^oC and Y is 5^oC

• X is -25^oC and Y is -10^oC

• X is 25^oC and Y is 30^oC

Tags

NGSS.MS-PS1-4

The Time Temperature graph shows the relationship between temperature and time as heat/energy is added. The substance is in the solid phase at Time = 0 minutes. Using the time temperature graph, at what temperature will the substance (not water) begin to boil?

• 10^oC

• 40^oC

• 80^oC

• 110^oC

Tags

NGSS.MS-PS1-4