At its heart, chemistry is the study of matter. Matter is just the physical stuff that makes up everything in the universe. Your phone, the air you breathe, the water you drink – it’s all matter.

Chemistry explores what this stuff is made of, what its properties are, and how it changes. When you cook an egg, the liquidy, transparent egg white turns solid and white. That’s a chemical change. When you dissolve sugar in tea, the sugar seems to disappear, but it's still there. That's a physical change. Chemistry explains why and how these things happen.

Understanding these changes is fundamental. It helps us develop new medicines, create stronger materials for buildings, and find better ways to produce energy. It’s a central science that connects physics, biology, geology, and environmental science.

Chemists, like all scientists, use a structured approach to understand the world called the scientific method. It’s not a rigid checklist, but a general process for asking questions and testing ideas logically.

Imagine you see your bread dough rising. That's an observation. You might ask, "What makes it rise?" That's your question.

You propose an answer: "Yeast in the dough creates a gas that inflates it." This testable explanation is a hypothesis. To test it, you design an experiment: make one batch of dough with yeast and another without. You analyse the results and find that only the dough with yeast rose. Your hypothesis was supported. The final step is to report your findings.

Everything around us can be described by its properties and the changes it undergoes. These fall into two categories: physical and chemical.

Water, for example, is a clear liquid at room temperature. Its density is about 1 gram per cubic centimetre. It freezes at 0°C and boils at 100°C. These are all physical properties. You can observe them without turning the water into something new.

You can't know that wood is flammable just by looking at it. You have to try to burn it. When wood burns, it turns into ash, smoke, and carbon dioxide. It becomes something completely different. Its ability to burn is a chemical property.

Just as there are two types of properties, there are two types of changes.

A key clue for a chemical change is the formation of a new substance. This might be indicated by a change in colour, the production of a gas (bubbles), the formation of a solid (a precipitate), or the release of heat or light.

These basic concepts are the building blocks of chemistry. By understanding them, you can start to see the world from a molecular point of view.