2.06 assessment review

Which statement best describes the rate of dissolving?

• All substances dissolve at the same rate.

• All substances dissolve at a fast rate.

• The rate of dissolving may be fast or slow.

• Rates of dissolving are usually slow.

How does cold water affect the speed of dissolving?

• Cold water slows down dissolving.

• Cold water speeds up dissolving.

• Cold water has no effect on dissolving.

• Cold water completely stops dissolving.

Jake is making dinner and is trying to dissolve salt into a pot of water. The salt is dissolving slowly. What should Jake do to speed up the rate of dissolving?

• He should put larger salt particles in the water.

• He should heat the water to a higher temperature.

• He should completely stop stirring the pot of water.

• He should slow down the speed he is stirring the pot.

What is a combination of two or more substances that are all solids?

• A mixture of solids

• A pure substance

• A solid group

• A state of matter

What happens to a solid substance when it breaks down and becomes part of a liquid substance?

• It disappears and no longer exists.

• It dissolves into the liquid substance.

• It reacts with the liquid substance.

• It turns into a liquid substance.

When some cooking oil is poured into a glass of water, it does not dissolve. How do you know this?

• You see a clear colorless mixture of oil and water.

• You see a layer of oil on top of the water.

• You see the oil and water as one part.

• You see the oil disappear in the glass of water.

What could you do to increase the rate that sugar dissolves in water?

• Decrease the temperature of the water.

• Increase the temperature of the water.

• Let the sugar dissolve by itself.

• Use sugar cubes instead of sugar granules.

Which water would you use to make salt dissolve the fastest?

• Cold water

• Hot water

• Ice water

• Room temperature water

What is all matter made up of?

• Atoms

• Balls

• Blocks

• Energy

Which of these statements describes the size of an atom?

• An atom is larger than a sheet of aluminum foil.

• An atom is small but can be seen with just our eyes.

• An atom is the size of a plastic building block.

• An atom is tiny and cannot be seen without magnification.