1. Density
an object’s mass per unit volume
units:

5. Toothpaste
Electricity
A star
Juice
Sound
The ocean
Fear
Peanut butter
Saliva
Helium
Democracy
Car exhaust
Gasoline
Paper
Bacteria
A cell
Wisdom
Heat
Dog
Wind
Atoms
Soil
DNA
Clouds
batteries

6. Directions Classify these words into TWO groups.
Give a name to each group.
Add one more example to each group.
Raise your hand when you are done.

7. Matter and Changes

8. matter: has volume (takes up space), and mass
can be solid, liquid or gas

9. chemistry: the study of matter and changes to matter

10. physical change: the chemical composition (makeup or parts) of the matter stays the same.
Ex: state changes (solid to liquid to gas), changing shape (ripping, squishing)

11. chemical change: a compound’s chemical composition (makeup) is changed – it becomes a new substance
ex: burning, rusting, reacting

12. Chemical or Physical Change?
burning paper
folding a piece of paper
the reaction of KI and Pb(NO3)2
combustion of gasoline
hammering gold into a ring
cutting a diamond
acid rain “melting” a statue
a pile of old iron rusting
separating water into H and O by using electricity

13. Which of the following is an example of a chemical change?
A. Ice cracking
B. Sugar dissolving
C. Milk souring
D. Lead melting

14. Which of these describes a pollution-producing process that involves only a physical change?
A. Coal with a high sulfur content is burned, producing gases that cause acid rain.
B. Chlorofluorocarbons are released, changing ozone in the upper atmosphere into oxygen.
C. Hot wastewater is discharged into a lake, lowering oxygen levels in the water.
D. Nitrogen oxide emissions combine with water vapor, producing nitric acid.

15. Which of the following processes is an example of a physical change associated with an oak tree?
A. Decomposition of bark by bracket fungi.
B. Starches and sugars being broken down during energy production.
C. Water and carbon dioxide being converted to glucose.
D. Evaporation of water from the surface of the leaves.

16. Which of the following represents a physical property?
a. Copper tarnishes to green when weathered.
b. Oxygen is flammable when ignited.
c. Iron rusts when exposed to oxygen.
d. Ice melts if left at room temperature.

17. Write down one unique example of a physical change you see at school.

18. Write down one unique example of a chemical change you see in your neighborhood.

21. Water

23. H2O

24. Ice

25. Dihydrogen monoxide

28. TAKES SHAPE AND VOLUME OF CONTAINER! FIXED VOLUME FIXED SHAPE
States of Matter
low temperatures
high temperatures
slow particle movement
fast particle movement
TAKES SHAPE AND VOLUME OF CONTAINER!
FIXED VOLUME
NO FIXED SHAPE
FIXED VOLUME FIXED SHAPE
Solid Liquid Gas

29. State Shape Volume Den-sity Particle motion Forces solid liquid gas
definite (fixed)
definite
high
slight vibration
liquid
not definite
medium
gas
low, varia-ble
very, very fast

30. Which state… Fixed volume and shape No fixed shape and no fixed volume
Fixed volume but no fixed shape
Takes the shape and size of its container
Takes the shape, but not the size of its container

31. Which state… Can be squeezed (compressed) into a smaller space?
Exists at a low temperature?
Has medium particle motion?
Has particles that just vibrate a little bit?

32. States of Matter and Transitions (Phases)
SOLID
SUBLIMATION
FREEZING
MELTING
DEPOSITION
EVAPORATION
LIQUID
GAS
CONDENSATION

33. Why does temperature change the state of a sample of matter?
Kinetic Theory: all matter is made of particles that are always moving.
Temperature: a measurement of Kinetic Energy (oC, K)
0 Kelvin: absolute zero: no particle movement
200 K is twice the particle movement of 100 K
Kinetic energy can overcome bond forces

34. low kinetic energy (KE)
high kinetic energy (KE)
Solid Liquid Gas

36. Bond forces hold particles together.
Kinetic energy may be great enough to break bonds between particles (in a gas)

37. State Shape Volume Density Particle motion Forces solid liquid gas
definite (fixed)
definite
high
slight vibration
Greater than KE
liquid
not definite
medium
Similar to KE
gas
low, varia-ble
very, very fast
Much less than KE

38. What transition? Ice turns into water Water turns into steam
Water turns into ice
Water vapor (gas) turns into rain in clouds
Water boils and turns to steam
An ice cube looks like it’s making steam!
Cream and sugar turns into ice cream.
Snow turns into water vapor.

39. Which state… Has the lowest Kinetic Energy?
Has very strong bond forces?
Has the highest Kinetic Energy?
Has bonds that are broken most easily?
Has bond forces similar to its Kinetic Energy?