Study Notes
Elements, compounds, and mixtures are fundamental concepts in chemistry. Element — a substance made of atoms with the same number of protons and cannot be split into anything simpler. Example: Carbon (C) is an element. Compound — a pure substance made up of two or more elements chemically combined and cannot be separated by physical means. Example: Water (H2O) is a compound. Mixture — contains different substances that are not chemically joined to each other. Example: Air is a mixture of gases like nitrogen and oxygen.
Exam Tips
Key Definitions to Remember
- An element is a substance made of atoms with the same number of protons.
- A compound is a pure substance made up of two or more elements chemically combined.
- A mixture contains different substances not chemically joined.
Common Confusions
- Confusing compounds with mixtures; compounds are chemically combined, mixtures are not.
- Misunderstanding that elements can be separated into simpler substances; they cannot.
Typical Exam Questions
- What is an element? An element is a substance made of atoms with the same number of protons.
- How is a compound different from a mixture? A compound is chemically combined, while a mixture is not.
- Give an example of a mixture. Air is a mixture of gases like nitrogen and oxygen.
What Examiners Usually Test
- Understanding the difference between elements, compounds, and mixtures.
- Ability to identify examples of elements, compounds, and mixtures.
- Knowledge of how elements are represented on the Periodic Table.