Practice Problems: Elements, Mixtures, and Compounds

Front

What is an Element?

Back

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Examples include hydrogen (H), oxygen (O), and gold (Au).

Front

What is a Compound?

Back

A compound is a substance formed when two or more elements chemically bond together. Compounds can only be separated into their constituent elements through chemical reactions. Example: Water (H2O) is a compound made of hydrogen and oxygen.

Front

What is a Mixture?

Back

A mixture is a combination of two or more substances that are not chemically bonded. Mixtures can be separated by physical means. Examples include air, salad, and saltwater.

Front

How are Compounds formed?

Back

Compounds are formed through chemical changes, where elements react with each other to create new substances.

Front

How are Mixtures separated?

Back

Mixtures can be separated by physical changes, such as filtration, distillation, or evaporation.

Front

What is the difference between a Compound and a Mixture?

Back

A compound is a chemical combination of elements, while a mixture is a physical combination of substances that retain their individual properties.

Front

Can elements be separated into simpler substances?

Back

No, elements cannot be separated into simpler substances by chemical means.

Front

What is a Homogeneous Mixture?

Back

A homogeneous mixture is a mixture that has a uniform composition throughout. Examples include saltwater and air.

Front

What is a Heterogeneous Mixture?

Back

A heterogeneous mixture is a mixture that does not have a uniform composition and the individual components can be seen. Examples include salad and sand.

Front

What is a Chemical Change?

Back

A chemical change is a process that involves the transformation of one or more substances into different substances, often involving a chemical reaction.