Elements, Compounds, and Mixtures

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) and oxygen (O).

Front

Which of the following represents an element? H2O, H2, NaCl, CaCO3

Back

H2

Front

What is a compound?

Back

A compound is a substance formed when two or more elements are chemically bonded together. For example, water (H2O) is a compound made of hydrogen and oxygen.

Front

How many elements are represented in the compound Na2CO3?

Back

3

Front

What is a mixture?

Back

A mixture is a combination of two or more substances that are not chemically bonded. Examples include air and salad.

Front

What cannot be broken down into other substances?

Back

Element

Front

What are atoms?

Back

Atoms are the smallest units of matter that make up all substances. They consist of protons, neutrons, and electrons.

Front

Which of the following is not a compound? HCl, Cl, NaCl, CO2

Back

Cl

Front

What is the difference between an element and a compound?

Back

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

Front

Can mixtures be separated by physical means?

Back

Yes, mixtures can be separated by physical means such as filtration, evaporation, or distillation.