# Electronics Handbook/Matter

## Matter

Matter refers to any physical quantity that has shape, can be measured, and has its own physical, chemical and electrical properties.

### Physical Properties

All matter exists in one of three states

1. Solid for instance an ice cube
2. Liquid for instance liquid water
3. Gas for instance water vapor

All matter has a mass M and a volume V that can be measured. The ratio of mass over volume defines the density of matter

$D = \frac{M}{V}$

### Chemical Properties

All matter is made up from Chemical Elements. There are about 128 Chemical elements have been discovered and tabulated in a table called Chemical Element Periodic Table invented by a Russian Scientist named Mendeli

Each Chemical Element has its own Atomic number and Mass . The Atomic number represents number of Protons in the Nucleus and number of Electrons on the orbits of Matter's Atom

E zm

### Sub Atomic Electric Charged Particles

Further study of matter has shown that atoms are made up of sub-atomic particles that carry Electric charge, called Electric Charged Particles. There are three basic types of charged particles:

1. Electron a sub-atomic particle that has Negative Charge with a Mass Me denoted by a symbol e-
2. Proton a sub-atomic particle that has Positive Charge with a Mass Mp denoted by a symbol p+
3. [neutron]] a sub-atomic particle that has Zero Charge with a Mass Mn denoted by a symbol no

## Matter Model

Since the discovery of charged particles scientific theory has developed. It is now theorised that all matter is made up from charged particles.

### Rutherford's Model

In 19__, Rutherford proposed a model of matter using electrons, protons and neutrons. According to Rutherford's model,

1. All matter has a Mass M a Volume V and a Density equal to the ratio of Mass over Volume. All matter exists in one of three states: solid, liquid or gas
2. All matter is made up from charged particles the smallest indivisible part still has the same characteristics
3. All matter has a nucleus made of protons and (with some exceptions) neutrons in the center and electrons orbiting around the nucleus
4. Usually the number of electrons in the orbits is equal to the number of protons in the nucleus.
5. Only electrons in the outermost orbits can participate in chemical reactions

### Bohr's Model

In 19__, Bohr proposed that

1. Each electrons orbit has a quanta of energy corresponding to an Energy Level Number n .
2. There are 4 Energy Level Number n = 1 ..4 . n = 4 has the highest energy level . n = 1 has the lowest energy level
3. When an electron moves from High Energy Level to Low Energy Level Electron then electromagnetic radiation is emitted of equivalent energy
4. En-1 - En = hf