Kinetic Particle Theory

State of matter	Properties	How are the particles arranged?	Explanation for the movement of the particles.	Inter-particles force	Inter-particle distance	Shape	Compression	Motion of particles
Solid	Fixed shape, Fixed volume,	-Molecules are closely packed in a regular pattern	-Vibrate about in fixed position	-Very strong attraction	-Close	Fixed shape	Cannot be compressed	Vibrate about at fixed position
	High density	-This accounts for high density of solids	-Very strong intermolecular bonds
			-This accounts for why solids have foxed volume shape
Liquid	No fixed shape, Fixed volume,	-Molecules are slightly further than that in the solid	-Free to move about between the molecules therefore no fixed shape	-Strong attraction	-Far apart	Take the shape of the container	Cannot be compressed	Random rotation and translation
	High density	-This accounts for high density of liquid	-Very strong intermolecular forces so there is fixed volume
Gas	No fixed shape, No fixed volume, Low density	-Molecules are very far apart	-High speed and move in a random manner	-Weak attraction	-Very far apart	Entirely fills the container	Easily compressed	Random rotation and translation
		-This accounts for low density of gas	-Intermolecular forces are negligible
			-No fixed volume
			-No fixed shape
			-Highly compressible

Experiment on Brownian motion

Apparatus: Microscope, Torchlight, Glass cell containing dust particles
Steps: 1) Set up a microscope
       2) Seal the glass cell containing some smoke particles and place them under the microscope
       3) Focus the microscope to see the smoke particles. the   smoke particles will appear as bright dots.
Observation: 1) Smoke particles move in random motion and         direction.
             2) The larger the particles, the slower the motion
Conclusion: Irregular motion of smoke is due to uneven           bombardment of air molecules of the smoke particles.

What are the effects of Brownian motion?

The effects of Brownian motion is seen in our everyday life. The most well-known effect is diffusion, the movement of particles from a region of higher concentration to a region of lower concentration. Many wonder why does diffusion occur and the most common answer is " concentration difference ". the more detailed explanation would be that the particles are constantly being hit by the air particles or water molecules and this causes them to move from their original location to another, causing them to spread in all directions. For example, when one sprays perfume in a corner of the room, the perfume particles in that region is constantly being bombarded by the surrounding air particles and there is no fixed direction. this causes the perfume particle to spread in all directions, or random directions, and soon the whole room is filled with the perfume particles. That is why when someone sprays perfume, the whole room can smell it.

What is Brownian Motion?

Brownian motion is the random moving of particles suspended in a fluid, resulting from their bombardment by the fast-moving atoms or molecules in the gas or liquid. As we all know, particles are always in constant random movement and this cause the bombardment. the direction of the force of atomic bombardment is constantly changing, and at different times the particle is hit on more than one side, leading to the seemingly random motion.  

Background Infomation

In 1827, the botanist Robert Brown, looking through a microscope at particles found in pollen grains in water, noted that the particles moved through the water but was not able to determine the mechanisms that caused this motion. Atoms and molecules had long been theorized as the constituents of matter, and many decades later, Albert Einstein published a paper in 1905 that explained in precise detail how the motion that Brown had observed was a result of the pollen being moved by individual water molecules. This explanation of Brownian motion served as definitive confirmation that atoms and molecules actually exist, and was further verified experimentally by Jean Perrin in 1908. 

Team Members

 Li Huankang, Benjamin Chan, Douglas Mok, Irman, Edmund, Javier Lian