Composition of Matter - Elements, Compounds, and Mixtures

What are the two fundamental properties that define matter?

• Color and texture

• Mass and volume

• Temperature and pressure

• Density and solubility

Why is it important for chemists to work with pure samples of matter?

• Pure samples are easier to store.

• It allows for better prediction of chemical behavior based on principles.

• Pure samples are always safer to handle.

• Pure samples are more aesthetically pleasing.

Which statement accurately describes a pure substance?

• It is a physical blend of two or more substances.

• Its composition can vary depending on the source.

• It always has a definite composition that does not change.

• It can be easily separated into its components by physical means.

How many types of atoms are in an element? (type a number in the blank)

Does water always have the same chemical composition (two hydrogens and one oxygen)?

• Yes

• No

• Sometimes depending on the temperature

Which of the following statements is true?

• A mixture always has the same chemical composition

• A compound always has the same chemical composition

• A mixture is always made up of the exact same ratio of elements

• A compound is physically blended together.

Is AIR classified as an element, a mixture or a compound?

• It can be either

• compound

• mixture

• element

What characteristic distinguishes a homogeneous mixture from a heterogeneous mixture?

• A homogeneous mixture has multiple phases, while a heterogeneous mixture has one phase.

• A homogeneous mixture has a uniform composition throughout, while a heterogeneous mixture does not.

• A homogeneous mixture is always a liquid, while a heterogeneous mixture can be solid or gas.

• A homogeneous mixture can be separated by physical means, while a heterogeneous mixture cannot.

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

• Cereal with milk

• Freshly squeezed orange juice with pulp

• Tang mixed into water

• Trail mix

Which of the following substances is classified as a heterogeneous mixture?

• Helium

• Glucose

• Table salt

• Non-homogenized milk