STATES OF MATTER

REVIEW

States of Matter•Mass & takes up space•No 2 pieces occupy the same

space at the same time•4 forms - depends on

temperature– Solids– Liquids– Gases– Plasma

Solids•Definite volume & shape•Not enough energy to move

– Crystalline – repeating geometric patterns

– Noncrystalline – amorphous no true form, thick liquids

Liquids

•Definite volume•No definite shape – takes shape

of container• Particles have enough energy to

move– Viscosity – property of how easily liquid flows

Gases

•No definite volume or shape•Takes volume & shape of

container•Particles have enough energy to

overcome attractive forces holding them together & fill the container

Plasma

•Like a gas•Lots of energy •Electrically charged, fast

moving particles– the sun, space shuttle, lightening

Kinetic Theory of Matter

•Matter is made of tiny particles in constant motion

• temperature, motion

•KE = energy of motion•PE = stored energy

Kinetic Theory of Matter

Thermal Expansion•Increase temp, increase

energy: particles move faster & further apart increasing the volume–Concrete slabs on bridge

Changing States of Matter

Solid Liquid GasMelting pt

Freezing pt

Boiling pt

Condensation

Sublimation

Evaporation

Heat of Fusion

•Energy required for a substance to change from a solid to a liquid

•Different for every substance•No temp Δ until complete

– Ice to water 0°C until done –334 kJ/kg for water

Heat of Vaporization

•Energy required for a substance to change from a liquid to a gas

•Different for every substance•No temp Δ until done

–Water to steam 100°C–2260kJ/kg for water

Freezing Point Depression•Decrease the freezing point of

water by dissolving particles in it–Salting icy roads & sidewalks

•Ice melts as freezing pt is lowered

– Ice cream makers•Ice Cream -3°C, Ice 0°C•Salt lowers freezing pt of ice so that ice cream can freeze

Boiling Point Elevation

• Increase in the boiling pt of water by dissolving particles in it

•Solute particles reduce how easily molecules get to surface to evaporate increasing bpt since water needs more energy

Part 2

Behavior of Gases & Fluids

•Pressure – amount of force per unit area (pascal, Pa) P = F/A

•Atm. pressure @ sea level 101.3kPa–Pressure decreases w/ elevation: fewer gas particles

•Gas Laws treat gases as ideal: no volume or attraction btwn molecules

Boyles Law•If you decrease the volume of a container of gas, the pressure of the gas will increase as long as temperature remains constant

•Movie: Men of Honor

Boyles Law:constant temperature

Pressure Volume

Charles Law•Volume of a gas

increases as temp increases if pressure remains constant–Absolute Zero lowest possible temperature no movement of particles

Charles Law:constant pressure

Temp. Volume

Fluids•Buoyancy – the ability of a

fluid (liquid or gas) to exert an upward force on an object immersed in it– Force = weight… Floats– Force < weight… Sinks– Force > weight… Rises

Archimedes’ Principle•Bouyant force on an object in

a fluid equals the weight of the fluid displaced by the object

Pascal’s Principle•Pressure applied to a fluid is

transmitted unchanged throughout the fluid–Ex. pistons, toothpaste

–P=F/A

Bernoulli’s Principle

•As the velocity of a fluid increases, the pressure on it decreases– Ex. air plane wing

Venturi Effect

•A fluid flows faster when forced through narrow spaces–Ex. windy cities