Everyday science
Chemistry is already in tap water, air, cooking and the materials around us. Start with something familiar and work back to the science.
Water
Water looks simple, but a glass of tap water is already a small chemistry lesson.
Air
Air is not one substance. It is a mixture of gases with very different chemical roles.
Kitchen chemistry
A kitchen is full of chemistry: dissolving, emulsions, acids, gases, heat and browning reactions happen there every day.
Chemistry at home
Paint, glass, detergents, metals, plastics and tap water make an ordinary home a surprisingly rich chemistry map.
Why does ice float?
Most solids are denser than their liquids. Water does the opposite around freezing: ordinary ice is less dense than liquid water.
How does soap remove grease?
Water and grease do not mix well. Soap helps because each surfactant molecule has one part that interacts well with water and another that prefers oily material.
Why does salt melt ice?
Salt does not heat the ice. It changes the conditions under which liquid water and ice can coexist by lowering the freezing point of the water.
Why does limescale form in a kettle?
The white deposit in a kettle is not simply 'dirt'. It comes from dissolved minerals in hard water, especially calcium compounds.
Why does soda fizz?
The bubbles were already hiding in the drink — as dissolved carbon dioxide.
Why does copper turn green?
Outdoor copper slowly builds a surface patina through reactions with its environment.
Why does metal feel colder?
Metal and wood can be at the same temperature but feel very different to your hand.
Why does a pencil write?
The dark core is not lead: it is mainly graphite mixed with clay.
Why does soap clean?
Soap molecules have one part that likes water and another that associates much better with oils.
Why does a cut apple turn brown?
Cutting the fruit brings enzymes, oxygen and phenolic compounds into contact.