Atom

An atom is the smallest unit of an element that retains the chemical properties of that element. Atoms are composed of three types of subatomic particles: protons, neutrons, and electrons.

Structure of an Atom

The center of an atom contains a nucleus, which is composed of protons and neutrons. The protons have a positive charge, and the neutrons have no charge (they are neutral). Surrounding the nucleus are the electrons, which have a negative charge and are found in energy levels or shells around the nucleus.

Protons, Neutrons, and Electrons

• Protons: Positively charged subatomic particles found in the nucleus of an atom. They determine the identity of the element.
• Neutrons: Neutral subatomic particles found in the nucleus of an atom. They add mass to the atom but do not affect its chemical properties.
• Electrons: Negatively charged subatomic particles found in energy levels or shells surrounding the nucleus. They are involved in chemical bonding and reactions.

Study Guide

1. What is an atom?
2. What are the three types of subatomic particles and their charges?
3. Where are protons and neutrons located in an atom?
4. Where are electrons located in an atom?
5. What is the significance of protons in determining the identity of an element?
6. How do electrons contribute to chemical bonding and reactions?

Understanding the structure and properties of atoms is fundamental to understanding the behavior of matter and the interactions between different substances.

[Atom] Related Worksheets and Study Guides:

• Properties of atomsScience • Eighth Grade
• Atomic Structure - Set IIChemistry • High School