Learn: Atoms, Elements and Compounds

Welcome!Today, we’ll explore atoms, elements, and compounds—the building blocks of all matter. Let’s dive into this fascinating topic step by step!

What is an Atom?An atom is the smallest particle of an element that can exist. Atoms are made up of three subatomic particles: protons, neutrons, and electrons. Understanding atoms helps us explain the properties of all substances around us.

Subatomic ParticlesThe three key subatomic particles are:Protons — positively charged particles found in the nucleus.Neutrons — particles with no charge, also in the nucleus.Electrons — negatively charged particles that orbit the nucleus.The number of protons determines the element.

What is an Element?An element is a substance made up of only one type of atom. Examples include oxygen, hydrogen, and gold. Each element has a unique number of protons, called its atomic number.

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

Representing Elements and CompoundsEach element is represented by a chemical symbol (e.g., O for oxygen, H for hydrogen). Compounds are shown using chemical formulas, which indicate the elements and their quantities (e.g., CO2 for carbon dioxide).

Mixtures vs. CompoundsA mixture is different from a compound. In mixtures, substances are physically combined and can be separated (e.g., salt and water). In compounds, substances are chemically bonded and cannot be separated as easily (e.g., water).

Review Time!Great work! You've learned about atoms, elements, and compounds. Let’s test your understanding with a few final questions.