The video tutorial explains the classification of matter into pure substances and mixtures. Pure substances are further divided into elements and compounds, while mixtures are categorized as homogeneous or heterogeneous. Examples of each type are provided, such as oxygen and water for pure substances, and saltwater and oil-water for mixtures. The video concludes with a summary and links to additional resources.

What are the two main categories into which matter can be classified?

• Pure Substances and Mixtures

• Gases and Liquids

• Elements and Compounds

• Solids and Liquids

Which of the following is an example of a pure substance?

• Air

• Sand and water

• Saltwater

• Oxygen gas

Tags

NGSS.MS-PS1-4

What defines a compound as a pure substance?

• It is composed of two or more different elements.

• It is composed of only one kind of element.

• It is a homogeneous mixture.

• It is a mixture of different substances.

Which of the following is NOT a pure substance?

• Water

• Brass

• Sodium chloride

• Ethanol

What is a homogeneous mixture?

• A mixture where the composition is uniform.

• A mixture where the composition is not uniform.

• A pure substance composed of one kind of element.

• A pure substance composed of two or more elements.

Which of the following is an example of a homogeneous mixture?

• Iron and sulfur

• Salt and water

• Sand and water

• Oil and water

What characteristic defines a heterogeneous mixture?

• Non-uniform composition

• Uniform composition

• Composed of two or more elements

• Composed of only one kind of element

Which of the following is an example of a heterogeneous mixture?

• Air

• Salt and water

• Brass

• Oil and water

Why does oil float on water in a heterogeneous mixture?

• Oil dissolves in water.

• Oil is less dense than water.

• Oil and water have the same density.

• Oil is denser than water.

Which of the following is a characteristic of air as a mixture?

• It is a heterogeneous mixture.

• It is a pure substance.

• It is composed of only one kind of gas.

• It is a homogeneous mixture.