«Give me matter, and I will construct a world out of it!».

Immanuel Kant[6]

Vocabulary

Task 1. Discuss with a partner.

1. Do you agree or disagree with the quotation above?

2. What is matter? What is the structure of it?

Task 2. Read the text « Theories of Matter » and say what t heories explain the structure of matter .

Theories of Matter

Matter is defined as the substance of objects that also takes up space and has mass. But matter also has various characteristics, so ancient scientists searched for a universal explanation for appearance, properties and behaviour of matter. One theory that explained some of the properties of matter is the Molecular Theory of Matter. This was followed by the Atomic Theory of Matter. There are still theories being developed that try to explain the true structure of matter in even more detail.

The original Molecular Theory of Matter stated that all matter consists of tiny particles called molecules. These particles are constantly moving and bouncing off each other like billiard balls. The Molecular Theory of Matter is also called the Kinetic Theory of Matter, because of the constant movement of the molecules. The motion of molecules is responsible for the phenomenon of heat. In other words, the faster the molecules are moving, the higher the temperature. When the molecules speed up or the material is heated sufficiently, the kinetic energy overcome the molecular attraction and the substance changes its state from a solid to a liquid. Likewise, when the kinetic energy of the molecules increases further, the material can change from a liquid to a gaseous state.

Molecules can be broken into smaller particles called atoms. The Atomic Theory of Matter states that all matter consists of extremely small particles called atoms. It was originally thought that atoms were the smallest possible particles, but that has since been proven incorrect. Atoms consist of even smaller particles called electrons, protons, and neutrons. A combination of protons and neutrons combine to form the nucleus of an atom. A popular model or picture of an atom that explains many of its properties and features is the solar system model of the atom. This model is also called the Bohr Model, named after Neils Bohr, who came up with the idea. It states that electrons rotate around the nucleus, similar to the planets revolving around the sun. The Atomic Theory explains electricity. When electrons break away from their nuclei, their motion results in electricity.

Since the Atomic Theory was formulated, many new particles have been discovered. The new theories concerning these particles and predicted particles attempts to explain every phenomena in physics. This is also called the Universal Theory of Matter. Also, there have been discovered that the proton and neutron themselves are made of even smaller particles, called quarks. These particles are then held together by particles called gluons. Finally, there is a theory that these sub-atomic particles are not particles at all, but really vibrating strings. The Quantum Theory of Matter states that at the very small sub-atomic distances, matter does not travel in continuous motion. Instead, it jumps from position to position in discrete or quantum leaps. This theory also states that particles spin in very discrete motion. The Uncertainty Principle states that with small particles, you cannot tell exactly where the particle and how fast it is going at the same time. The newest theory is that matter consists of tiny strings of material, instead of round balls. The String Theory seems to explain many phenomena for both large systems and at the quantum level. But many scientists claim that it is simply a mathematical exercise, since it cannot be proven or disproven.

 (From Theories of Matter by Ron Kurtus)