Atoms & Classifying Matter

A substance contains two different components joined by physical means. Which best describes the substance?

• element

• compound

• mixture

• water

Which is a homogeneous mixture?

• pizza

• vinegar

• concrete

• woven fabric

Which represents a compound?

• air

• iron

• soil

• water

Which could best be separated into simpler substances by filtration and evaporation?

• atom

• element

• compound

• solution

Salt and water are stirred together in a beaker. The solid salt particles seem to disappear in the water. Which is the best explanation for the product that is formed?

• A solvent has been created.

• A solution has been created.

• A compound has been created.

• A new element has been created.

Why is carbon an element and not a compound?

• All carbon atoms have the same number of protons.

• Carbon bonds easily with oxygen, but not helium.

• Carbon is found in all living organisms.

Which of the following is NOT a pure substance?

• water

• helium gas

• table salt

• air

Which of the following states of matter has particles with the lowest level of energy?

• solid

• liquid

• gas

Which of these are broken down during chemical, but not physical, changes?

• elements

• mixtures

• compounds

• solutions

Which is a compound?

• Nitrogen (N₂)

• Neon (Ne)

• Ozone (O₃)

• Ammonia (NH₃)