​The body uses the substances in air, food, and water that we breathe, eat, or drink to carry out chemical reactions to keep us alive.

​These substances are made up of matter.​

What then is the nature of matter?​

Learning Objectives

​By the end of the week, you will be able to:

1. Define atom and name all the subatomic particles​.

2. Distinguish between elements and isotopes.

3. Define chemical compounds​ and give at least three examples of chemical compounds.

4. State and explain the two main types of chemical bonds.

​Lesson Breakdown

​Lesson 1​: Atoms

​Lesson 2: Elements and Isotopes

Lesson​ 3: Chemical Compounds

Lesson​ 4: Chemical Bonds​

​Lesson 1​

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Atoms

Atoms

​By the end of Lesson 1, you will be able to answer the following Key Questions!

1. What is an atom?

2. What three subatomic particles make up atoms?

3. What are the characteristics of the subatomic particles?​

• ​Atom is the basic unit (or the smallest particle) of matter.

• The subatomic particles are:

  1. protons

  2. neutrons

  3. electrons

• Protons and neutrons together form the nucleus of an atom.​​

• A strong force of attraction binds protons and neutrons together.​

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• ​In an atom the number of protons is equal to the number of neutrons.

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• ​Electrons are arranged in a series of shells or orbitals.

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• Atoms are electrically neutral​ because they have equal numbers of protons (+) and electrons (-) and the opposite charges cancel out.

​Properties of the subatomic particles.

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​Note:

a.m.u. means atomic mass unit

​Thank You

Lesson 2

Elements and Isotopes