Unit 2 Semester Test

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

A compound is a substance formed when two or more elements are chemically bonded together. An example is carbon dioxide (CO2), which consists of carbon and oxygen.

A homogeneous mixture is a mixture that has a uniform composition throughout. An example is saltwater, where the salt is evenly distributed.

A heterogeneous mixture is a mixture where the components are not uniform and can be easily distinguished. An example is a salad.

Iron (Fe) is an element.

A mixture is a combination of two or more substances that are not chemically bonded and can be separated by physical means.

An element is a single type of atom, while a compound is made up of two or more different types of atoms chemically bonded together.

The chemical formula for carbon dioxide is CO2.

Carbon dioxide is a gas at room temperature.

An example of a homogeneous mixture is vinegar.