EASY READ Science

Science is the study of the natural world. Scientists are men and women who investigate matter, energy, forces, air, water, Earth, space, and living things. They make careful...

EASY READ Solid, liquid or gas?

Most substances exist in one of three states: solid, liquid or gas. They change from one state to another when they are heated or cooled. Water is a liquid at room temperature, but...

EASY READ What are things made of?

Everything in the Universe, including the air we breathe, is made up of extremely tiny building blocks called atoms. They are so small, you would not even be able to see one under...

EASY READ Why is carbon an important element?

One of the most important chemical elements is carbon. This is because it is the main element in all living things. Unlike most elements, pure carbon can exist in different forms...

EASY READ What is a chemical reaction?

Substances join with others to form new substances in what is called a chemical reaction. Reactions can take place naturally. For example, the food we eat is changed into energy...

EASY READ What is a solution?

Stir a teaspoon of table salt into a glass of water, and the salt disappears. However, tasting the water shows the salt is still there. It has dissolved. The crystals of salt have...

EASY READ What is oxygen used for?

Oxygen is one of the commonest chemical elements on Earth. It is found in most minerals, chemicals that form rocks. Oxygen makes up one fifth of the air. Joined with hydrogen, it...

EASY READ What is a metal?

More than three-quarters of all elements are metals. They share many properties. Nearly all metals are solid at room temperature. Many are strong and hard, which makes them useful...

EASY READ What are the properties of solids?

Besides their chemical make-up (what kind of atoms they have), solid materials have different qualities or properties. These include, for example, whether they are hard or soft...

EASY READ What are the properties of liquids?

A liquid's molecules can move around more than in solids. This means a liquid can change shape and flow, although, like a solid, it still takes up the same volume. Liquids cannot...

EASY READ What are the properties of gases?

The molecules in gases are much more widely spaced than those in liquids, so they move about more quickly. Gases have no shape of their own, so they spread to fill whatever...

EASY READ What are the properties of water?

Water is a molecule. It is made up of two chemical elements: hydrogen (chemical symbol H) and oxygen (O). Each atom of oxygen is bonded to two hydrogen atoms. This is why water has...

EASY READ Why do things float or sink?

Why do some things float and other things sink? It depends on the density of the object. Density is a measure of how packed together an object’s matter (atoms and molecules) is...

EASY READ What are different kinds of materials used for?

A material is anything made of matter. This includes everything we can see, from the air to our own skin. But often when we use the word “materials” we mean materials that are...

EASY READ What is recycling?

Turning waste into new products and materials is called recycling. It is one of the “three Rs”: Reduction, Reusing and Recycling. Reducing waste means buying fewer products and...

EASY READ What is a force?

Objects do not move by themselves. Anything that pushes or pulls an object is called a force. A breath of wind, a car engine, a magnet or an elastic band are all examples of things...

EASY READ What causes motion?

Motion is any kind of movement. Motion is caused by forces. A stationary object does not move unless a force acts on it to start it going. Once it is moving, it carries on at the...

EASY READ What is pressure?

Pressure is the force exerted by something over a certain area. A nail goes into wood easily because the force hammering it in is concentrated on to the tiny area of the nail's...

EASY READ What is gravity?

Gravity is an invisible force that attracts objects to one another. Every object in the Universe, from a pen to a planet, has gravity, but bigger objects have more gravity than...

EASY READ How do machines work?

Machines are designed to make work easier and quicker to complete. They use forces to do different jobs. Even complex machines are made up of a few kinds of simple machines...

EASY READ What is friction?

Friction is a force that tries to stop things moving. It is produced when two surfaces rub together. Rough surfaces produce more friction than smooth ones. Friction can cause...

EASY READ Where does energy come from?

When you are feeling very active, someone may tell you that you have a lot of energy. Energy is the ability to do something. It takes many different forms. Fuel contains energy: it...

EASY READ What is heat?

Heat is the energy an object has when its molecules are moving or vibrating (shaking). The hotter the object is, the more its molecules move. In solids, the molecules may vibrate...

EASY READ How is light made?

During the day, the world is lit by light rays from the Sun. Light is only one kind of energy which the Sun produces (heat and ultraviolet radiation are among the others). Light...

EASY READ How are colours produced?

Sunlight—bright white light—is a mixture of all the colours of the rainbow. This is called the spectrum of light. The different colours can be seen when a beam is shone through...

EASY READ What is electricity?

Electricity is an extremely useful form of energy. It can easily be changed into other forms of energy, such as light, heat and sound energy. Current electricity is easy to use...

EASY READ What is magnetism?

Magnetism is a force that attracts some objects to other objects. We cannot see it, but it is all around us since the Earth itself produces a magnetic field. A magnet is a piece of...

EASY READ What is sound?

Sound is made when something vibrates (shakes). The molecules in the air (or a liquid or solid) are rapidly pushed together and pulled apart. Musical instruments make pleasing...

EASY READ Science glossary