1.1B Kinetic Theory

All matter can exist in different forms called ______ __ ______. What does it depend on?

states of matter

it depends on temperature and pressure

States of matter are characterized by what?; the average kinetic energy is directly related to the ___________ of the system

energy of the particles

temperature

What is Temperature?

a measure of the average kinetic energy (E_k)of the particles of a substance

What is the State of Matter at a given temperature and pressure is determined by?

the strength of the inter-particle forces (forces between the particles)

Tell me the qualities of solids, liquids, and gases.

	Solid	Liquid	Gas
Packing	Particles close packed	Particles more spaced	Particles spread out
Inter-Particle Forces	Strong (more attraction)	Weaker	Negligible
Particle Motion	Particles vibrate in position	Particles slide over each other, vibrate, rotate, translate	Particles move freely, vibrate, rotate, translate (faster than liquid)
Shape	Fixed shape	No fixed shape (takes shape of container)	No fixed shape (expands and occupies available space)
Volume	Fixed volume	Fixed volume (don't compress easily)	No fixed volume

What is another term for gases and liquids? Why are they called that?

fluids due to their ability to flow

What is Diffusion?

process by which particles of a substance become evenly distributed, as a result of random movement

What is Kinetic Energy? What is its symbol? How do you calculate it?

the energy associated with movement or motion (E_k)

E_k=1/2 mv²

m = mass in grams

v = velocity in m/s

Kinetic energy of various particles at the same temperature is _____. This gives the inverse relationship between ________ and ____

equal

velocity and mass

(if 2 different particles have the same kinetic energy, their temp. will be the same. That means regardless of the their size or speed [velocity], they have the same amount of energy)

(remember E =1/2mv²)

Since kinetic energy increases with temperature, as particles move faster, what happens to the particles?

they can overcome inter-particle forces and change state

State changes occur at a fixed ___________ and ________ for each substance

temperature and pressure

What is the relationship between states of matter?

Define Sublimation

direct inter-conversion solid to gas without going through the liquid phase. Characteristic at atmospheric pressure of some substances like dry ice.

Define Deposition

reverse of sublimation, changes from gas to solid (like frosting)

Define Vaporization

the change in state of matter from liquid to gas. It can be accomplished through evaporation or boiling

Define Evaporation

change in state that occurs only at the surface of a liquid and at a temperature below the boiling point.

When heat is absorbed from the surroundings, particles at the surface acquire enough kinetic energy to vaporize and escape.

Define Boiling

volume phenomenon, happens throughout a liquid

• characterized by particles leaving throughout the body of the liquid

• forming bubbles

Define Boiling Point

when all molecules in a liquid have enough kinetic energy to change into a gas.

Define Vapour Pressure. What is its relation to Evaporation and Boiling?

the pressure exerted by a liquid on the walls of a container.

• During evaporation, vaporization is slow because the vapor pressure is less than atmospheric pressure.

• Boiling occurs when vapor pressure = atmospheric pressure