1. States of Matter Section 16.1 http://www.harcourtschool.com/activ ity/states_of_matter/ http://www.harcourtschool.com/activ ity/states_of_matter/

2. Kinetic Theory Kinetic Theory Kinetic Theory All matter is composed of small particles All matter is composed of small particles Particles are in constant random motion Particles are in constant random motion Particles collide with each other and the walls of their containers constantly Particles collide with each other and the walls of their containers constantly When particles collide- small amounts of energy are lost When particles collide- small amounts of energy are lost Solids- definite shape and volume- particles have strong attraction for each other, preventing motion Solids- definite shape and volume- particles have strong attraction for each other, preventing motion

3. Solids Thermal energy causes the particles to vibrate – KE Thermal energy causes the particles to vibrate – KE PE also causes some vibration- (energy due to the forces that act within or between particles) PE also causes some vibration- (energy due to the forces that act within or between particles) Higher temperatures- more vibration Higher temperatures- more vibration Temperature- the average KE of particles in a substance Temperature- the average KE of particles in a substance

4. Particle Motion No particle motion- absolute zero- 0K No particle motion- absolute zero- 0K Geometric arrangement of particles in a solid- determines chemical & physical properties of a solid Geometric arrangement of particles in a solid- determines chemical & physical properties of a solid Solids- particles are closely packed Solids- particles are closely packed From solid to liquid- in solids, particles move slowly From solid to liquid- in solids, particles move slowly Heat is added-particles move faster Heat is added-particles move faster Eventually solid particles are moving fast enough- have enough KE- to overcome the attractive forces between the particles and escape the solid Eventually solid particles are moving fast enough- have enough KE- to overcome the attractive forces between the particles and escape the solid

5. Particle Motion Melting Point- temperature at which a solid begins to liquefy. Melting Point- temperature at which a solid begins to liquefy. Heat of fusion- the amount of energy required to change a substance from the solid phase to the liquid phase at its melting point Heat of fusion- the amount of energy required to change a substance from the solid phase to the liquid phase at its melting point Particles of a liquid have more KE than particles of a solid Particles of a liquid have more KE than particles of a solid There is enough energy for particles to move past each other There is enough energy for particles to move past each other

6. Particle Motion Particles of a gas-have enough KE to overcome the attractions between them completely Particles of a gas-have enough KE to overcome the attractions between them completely Spread and fill the containers Spread and fill the containers Liquid to gas- some particles of a liquid move faster than others and escape the attractive forces of other particles- allows them to enter the gas phase Liquid to gas- some particles of a liquid move faster than others and escape the attractive forces of other particles- allows them to enter the gas phase Evaporation & Boiling- liquid into gas Evaporation & Boiling- liquid into gas Evaporation-particles must have enough KE to escape the attractive forces of the liquid Evaporation-particles must have enough KE to escape the attractive forces of the liquid

7. Particle Motion Boiling- the T at which the P of a vapor in the liquid is equal to the external P acting on the surface of the liquid Boiling- the T at which the P of a vapor in the liquid is equal to the external P acting on the surface of the liquid Heat of vaporization- amount of energy required to overcome the pressure at the surface of the liquid (E needed to boil) Heat of vaporization- amount of energy required to overcome the pressure at the surface of the liquid (E needed to boil) Diffusion-spreading of particles throughout a container until they are uniformly distributed Diffusion-spreading of particles throughout a container until they are uniformly distributed

8. Heating Curve A B C D E A- ice is being heated. B- ice is melting- heat of fusion - melting point C- liquid is heated up D- liquid is changing to vapor- heat of vaporization- boiling point. E - vapor is increasing in temperature

9. Temperature & Matter Plasma-gas consisting of positive and negative particles- most common state of matter in universe Plasma-gas consisting of positive and negative particles- most common state of matter in universe When temperature increases- substances expand- thermal expansion When temperature increases- substances expand- thermal expansion When temperature decreases-substances contract When temperature decreases-substances contract Thermometers-energy is added- particles of the liquid move faster & farther apart-forces fluid upward through the thermometer Thermometers-energy is added- particles of the liquid move faster & farther apart-forces fluid upward through the thermometer

10. Temperature & Matter Water Hot air balloons rise- higher temperature= expansion = lower density = rises Hot air balloons rise- higher temperature= expansion = lower density = rises Water Water Has + and – regions Has + and – regions Decrease in temperature-particles get closer together Decrease in temperature-particles get closer together - from one particle attracts to + of other molecule - from one particle attracts to + of other molecule Empty spaces in ice are greater than those in water- ice is less dense than water Empty spaces in ice are greater than those in water- ice is less dense than water Water expands from liquid to solid Water expands from liquid to solid

11. Solid Amorphous solid-solid that softens and gradually turns into a liquid over a large temperature range – don’t form crystals Amorphous solid-solid that softens and gradually turns into a liquid over a large temperature range – don’t form crystals Liquid crystals start to flow during the melting phase but do not lose their ordered arrangement completely Liquid crystals start to flow during the melting phase but do not lose their ordered arrangement completely

12. Liquid Crystals Highly responsive to temperature changes and electric fields. LCD displays in watches, clocks, calculators, computers, TVs Highly responsive to temperature changes and electric fields. LCD displays in watches, clocks, calculators, computers, TVs Liquid crystals start to flow during the melting phase but do not lose their ordered arrangement completely, retaining their geometric order in specific directions Liquid crystals start to flow during the melting phase but do not lose their ordered arrangement completely, retaining their geometric order in specific directions