1. Matter and energy

2. Matter?
Anything that has mass and volume (takes up space)

3. Law of conservation of mass
Mass cannot be created or destroyed

4. Energy?
Ability to do work on matter
Potential
kinetic

5. Law of conservation of energy
Energy cannot be created or destroyed, only transferred into another form
Energy can be converted into mass and mass into energy (E = mc2)

7. Lab Discussion: Did we Turn the penny into gold?
Summarize the procedure for the lab
Describe what you observed during the experiment.
What do you think happened to turn the penny silver?
What do you think happened to turn the penny gold?
Do you think you made real gold? Why or why not?
How could you find out?

9. Physical properties of matter
Viscosity – resistance to flow
Conductivity – ability to allow heat/electricity to flow
Malleability – ability to be hammered without shattering
Hardness – scratch test
Melting point – temperature at which a solid changes to a liquid
Boiling point – temperature at which a liquid changes to a gas
Density – ratio of an object’s mass to its volume (m/v)

10. Chemical properties of matter
Flammability – material’s ability to burn in the presence of oxygen
Reactivity – how easily one substance combines with another
What did we make?

11. Physical Changes vs. Chemical changes
Physical change: change in matter that changes some properties but the substances within the material remains the same
Change of state
Can often be reversed (not always)
Change in shape
Chemical change: change in matter when a substance reacts to form a new substance
Change in color (new color not blending)
Production of a gas
Formation of a precipitate

12. Identifying a Chemical Change
Table 2.1 Identifying Chemical Changes
Test tube
Starting Solution
Solution Added
Observation
Test Tube A
Test Tube B
Test Tube C

13. Quick lab questions?
In which test tubes did you observe a chemical change?
What evidence do you have that a chemical change did occur?
If you did not observe a chemical reaction, how would you be able to tell if there was in fact a reaction in that test tube?

14. Changes of state in matter

15. Solids, Liquids, Gases
Materials can be classified as solids, liquids, or gases based on whether their shape and volume are definite or indefinite.
Definite – fixed, does not change
Indefinite – can change based on container it is put in.

16. Solids Definite shape and definite volume
(definite: changing the container does not change the shape)
Atoms move but in fixed locations
Definite shape does not mean the shape can never change.
Particles have strong attraction and cannot slide past each other

17. Liquids Indefinite shape, definite volume
Takes the shape of the container its in
Only fills up the space of the same volume as the liquid
Particles have some attraction but can slide past each other

18. Gases No definite shape or definite volume
Takes the shape of the entire container
Gases move at an average of 1600 km/hr
Attraction between particles is so weak it can be ignored

19. Other States of Matter
On earth almost all matter is solid, liquid, or gas
In the universe 99% of all matter exists as plasma
Plasma: very high temps
atoms at very high temperatures have been stripped of their electrons
Plasma made of 2 particles = nuclei and electrons
Bose-Einstein Condensate: very low temps
atoms behave as if they are one single atom
Atoms almost stop moving and clump together as one super atom

20. Kinetic theory
All particles of matter are in constant motion

21. Kinetic theory in gases
Particles in a gas are in constant random motion
Motion of one particle is unaffected by the motion of other particles unless they collide
Forces of attraction among particles can be ignored under ordinary conditions

22. Factors Affecting Gas Pressure
Pressure = force over area
Gas Pressure (closed container) = collisions between particles of a gas and the walls of the container cause the pressure
Factors Affecting Gas Pressure
Temperature (T)
Increase in (t) = increase in (p)
Decrease in (t) = decrease in (p)
Volume (V)
Increase in (v)= decrease in (p)
Decrease in (v) = increase in (p)
# of particles (n)
Increase in (n) = an increase in (p)
Decrease in (n) = a decrease in (p)

23. Boyles Law
Pressure is inversely proportional to volume when temperature and # of particles is constant

24. Charles Law
Volume is directly proportional to temperature when pressure and # of particles is constant

25. Gay-Lussac’s Law
Pressure is directly proportional to temperature when volume and #of particles are constant

26. Combined Gas Law
Relationship between pressure, volume, and temperature when # of particles is constant

27. Absolute Zero Temperature of 0 Kelvins ( -273 ◦C)
Represents the lowest possible temperature
Cannot reach absolute zero

28. Add your gas law equations to your reference page for tests
All temperatures must be in Kelvins! You will have to convert out of Celsius(˚C = K)
Add your gas law equations to your reference page for tests

29. Steps to Working Gas Law Problems
Write down the variables from the problem
Change all temperatures to Kelvins
Figure out which equation to use
Plug in the variables to the equation
Solve!

30. Phase changes in matter

31. SOLID AND LIQUID PHASES
MELTING: SOLID TO LIQUID
Requires energy to heat the ice to make it melt
endothermic
FREEZING: LIQUID TO SOLID
Releases energy to turn the water into ice
exothermic

32. LIQUID AND GAS PHASES VAPORIZATION: LIQUID TO GAS
Requires energy to turn the liquid into a gas
endothermic
CONDENSATION: GAS TO LIQUID
Releases energy to make the water vapor into droplets
exothermic

33. SOLID AND GAS PHASES SUBLIMATION: SOLID TO GAS
Absorbs energy to make carbon dioxide gas
endothermic
DEPOSITION: GAS TO SOLID
Releases energy when water vapor forms snow
exothermic

34. Phase change diagram for water

35. Why does the temp. not change during a phase change?
All the energy is being used to break apart or bring together the atoms
There is no change in speed of particles so there is no change in temp.
Temperature measures speed of particles

36. Melting/Freezing Point
Same temperature
If you are heating a substance
Melting point
If you are cooling a substance
Freezing point
Freezing and melting point for water are both 0◦C