Chapter 7

there are 3 different states of matter-solid,liquid and gas.

properties of solid:-

• fixed shape and volume
• hard and rigid
• high density
• incompressible

properties of liquid-

• fixed volume but no fixed shape
• high density
• incompressible

properties of gas-

• no fixed shape or volume
• low density
• compressible

Kinetic model of matter

All matter are made up of tiny paricles called atoms or molecules(chemistry) and are always in motion.

arrangement of particles in solid-

• closely packed and in a regular pattern;high density

movement-

• vibrate about fixed position only and is held in position by intermolecular bonds;fixed volumes and shapes.

arrangement of particles in liquid-

• randomly arranged,and are further apart;high density

movement-

• free to move about and have attractive forcedbetween particles;fixed volume but no fixed shape.

arrangement of particles in gas-

• very far apart and occupies any space available;low density

movement-

• little attraction and move randomly at very high speeds;no fixed volume and shape but highly compressible

strength of intermolecular force(weak to strong) :gas,liquid,solid

relative distance between particles(close to far apart) :solid,liquid , gas

Brownian motion is the random or irregular motion of smoke particles in air(occurs only in fluids)

Effects of temperature on molecular motion:

-higher temperature-particles becomes more vigorous and agitated(vice versa),but WHY?

this is because particles hit one wnother vigoruously and frequently. Air molecules have greater speeds at higher temperaures. When temperature increases,a larger amount of thermal energy is converted to kinetic energy of air molecules.

Brownian Motion:

Done! :D