A symbol of element is the chemical symbol written in short form to represent a particular element. Some elements are represented by the first letter of its name. Examples:

Element	Symbol
Fluorine	F
Hydrogen	H
Iodine	I
Nitrogen	N
Oxygen	O
Phosphorus	P
Sulphur	S
Carbon	C
Vanadium	V

If there are two or more elements that have mane start with the same alphabet letter, a second letter is added to differentiate between these elements. The second letter used is always lowercase. Examples:

Elements	Symbol
Bromine	Br
Calcium	Ca
Chlorine	Cl
Chromium	Cr
Magnesium	Mg
Manganese	Mn
Neon	Ne
Nickel	Ni
Silicon	Si
Helium	He
Argon	Ar
Aluminium	Al
Zinc	Zn
Platinum	Pt

Some elements are represented by their Latin names. Example:

Elements	Latin Name	Symbol
Copper	Cuprum	Cu
Iron	Ferrum	Fe
Lead	Plumbum	Pb
Mercury	Hydrargyrum	Hg
Potassium	Kalium	K
Silver	Argentum	Ag
Sodium	Natrium	Na
Tin	Stannum	Sn

(Notes: You MUST Memorise the symbol for all these 31 elements)

Brownian Motion

1. Brownian motion is the physical phenomenon that tiny particles immersed in a fluid move about randomly.
2. A fluid can be a liquid or a gas.
3. Brownian movement, an example of diffusion, supports the kinetic theory of matter.
4. Examples of Brownian movement are
   1. movement of smoke particles in air
   2. movement of pollen grains in water

Conclusion : The rate of diffusion is highest in gas and lowest in solid.

Proof of Particle Theory of Matter - Diffusion

In SPM, you need to know

1. diffusion is one of the proofs of the particle theory of matter.
2. the definition of diffusion.
3. diffusion in solid, liquid and gas
4. factors that affect the rate of diffusion and the related experiments.

What is Diffusion?

1. Diffusion is a process of spreading a substance from a region of high concentration to a region of low concentration.
2. It occurs when the particles of the substance move through the space between the particles of another substance.
3. Figure below shows how the bromine particles diffuse into the air.
4. Diffusion occurs in solid, liquid and gas.
5. The rate of diffusion is highest in gas and lowest in solid.
6. Diffusion is proof of the particle theory of matter.

MUST KNOW!

• The rate of diffusion is highest in gas and lowest in solid.
• Diffusion is the proof of the particle theory of matter.

1. Matter is anything that occupies space and has mass.
2. The particle theory of matter states that matter is made up of a large number of tiny and discrete particles.

Particle Theory of Matter:  Matter is made up of a large number of tiny and discrete particles.

Types of Particles

1. Particles can exist as atoms, molecules or ions.
2. Atom is the smallest, indivisible particle of an element.
3. Molecules are particles that made up of two or more atoms.
4. Ions are particles that carry charge.
   1. Positive ion – Cation
   2. Negative ion - Anion