Pure Substances and Mixtures Review

What is a pure substance?

• A combination of two or more substances.

• A substance that is not combined with anything else.

• A type of mixture.

• A substance that can be easily separated into pure substances.

Which of the following is an example of a colloid?

• Salt dissolved in water.

• Sand mixed with water.

• Gel.

• Sugar and water shaken together.

What is the main characteristic of a solution?

• It is cloudy and the substances settle to the bottom.

• It is a pure substance.

• It is a uniform mixture where one substance is dissolved evenly throughout another.

• It is a mixture that can be easily separated by settling or sifting.

What happens when you shake a container of sand and water?

• The sand dissolves completely in the water.

• The sand and water form a solution.

• The sand will settle to the bottom of the container and the water will become cloudy.

• The sand and water form a colloid.

Tags

NGSS.MS-PS1-2

What is an emulsifier?

• A substance that makes a solution clear.

• A substance that can be added to mixtures to allow the liquids to remain completely mixed.

• A substance that separates a colloid.

• A substance that helps to settle the particles in a suspension.

What is the 'base' in an emulsion?

• The solid part of the mixture.

• The substance that is broken into tiny droplets.

• The liquid in which the droplets are dispersed.

• The substance added to make the mixture clear.

Which of the following is not a pure substance?

• Water

• Oxygen

• Wood

• Diamonds