1. Matter: Properties & Change

2. Physical properties
Physical properties can be observed or measured without changing the identity of the matter.
Basically, properties you notice when using one of your five senses:
Feel - mass, volume, texture
Sight - color
Hear
Smell
Taste

3. Physical properties of matter are categorized as either: Intensive or Extensive:
Intensive - Properties that do not depend on the amount of the matter present.
Color
Odor
Luster - How shiny a substance is.
Malleability - The ability of a substance to be beaten into thin sheets.
Ductility - The ability of a substance to be drawn into thin wires.

4. Conductivity - The ability of a substance to allow the flow of energy or electricity.
Hardness - How easily a substance can be scratched.
Melting/Freezing Point The temperature at which the solid and liquid phases of a substance are in equilibrium at atmospheric pressure.
Boiling Point - The temperature at which the vapor pressure of a liquid is equal to the pressure on the liquid (generally atmospheric pressure).

5. More Physical Properties
Density is a very important property.
It is the amount of matter in a given volume.
Density = Mass / Volume

7. A. Physical Properties
Physical properties can be described as one of 2 types:
Extensive Property
depends on the amount of matter present (example: length)
Intensive Property
depends on the identity of substance, not the amount (example: scent)

8. B. Extensive vs. Intensive
Examples:
boiling point
volume
mass
density
conductivity
intensive
extensive

9. Extensive - Properties that do depend on the amount of matter present.
Volume -
A measurement of the amount of space a substance occupies.
*Length

10. V is for Volume
Briefly, volume is the amount of space something takes up.
Whether it’s a speck of dust or Jupiter, all matter takes up space.

11. Measuring the volume of…
Liquids:
Graduated cylinder
Displacement method
Measured in liters (L) & milliliters (mL)
Solids:
Length x width x height
Gases:
Since a gas expands to fill its container, if you know the volume of the container, you know the volume of the gas.

12. Density - The mass of a substance divided by its volume
Density is an important physical property. Density is the mass of a substance per unit volume.
Volume is the amount of space an object occupies.

13. C. Density – a physical property
Derived units = Combination of base units
Volume (m3 or cm3 or mL)
length  length  length
Or measured using a graduated cylinder
1 cm3 = 1 mL
1 dm3 = 1 L
Density (kg/m3 or g/cm3 or g/mL)
mass per volume
D = M V

14. C. Density V = 825 cm3 M = DV D = 13.6 g/cm3 M = (13.6 g/cm3)(825cm3)
An object has a volume of 825 cm3 and a density of 13.6 g/cm3. Find its mass.
GIVEN:
V = 825 cm3
D = 13.6 g/cm3
M = ?
WORK:
M = DV
M = (13.6 g/cm3)(825cm3)
M = 11,220 g
M = 11,200 g

15. C. Density D = 0.87 g/mL V = M V = ? M = 25 g V = 25 g 0.87 g/mL
A liquid has a density of 0.87 g/mL. What volume is occupied by 25 g of the liquid?
GIVEN:
D = 0.87 g/mL
V = ?
M = 25 g
WORK:
V = M D
V = 25 g
0.87 g/mL
= mL
V = 29 mL

16. Physical Properties - Examples
Other physical properties include:
Color
Hardness
Odor
Taste
State of matter
Texture
Luster (shine)
Flexibility
Heat conductivity
Electrical conductivity
Solubility (ability to dissolve in water.)
Shape
Viscosity
Ductility
Malleability

17. D. Chemical Properties Chemical Property
describes the ability of a substance to undergo changes in identity

18. Chemical properties A common chemical property is reactivity.
Reactive to oxygen
Reactive to air
Reactive to water…
Notice that chemical properties aren’t EASY to observe, unlike physical properties.

19. Chemical properties - Examples
Examples of chemical properties include:
The ability to burn
Ability to tarnish
Ability to rust
Ability to decompose
Ability to react with other chemicals
Instability
Ability to do acid/base reactions

21. Physical vs. Chemical
Physical properties: observe without changing the identity of the substance
Chemical properties: observe only when the identity changes
How do you know if it is chemical or physical?
If it CHanges, it’s CHemical

22. E. Physical vs. Chemical Properties
Examples:
melting point
flammable
density
magnetic
tarnishes in air
physical
chemical

23. Chemical and physical properties – So what?
Titanium is very strong and doesn’t rust, so it is often used in jet engines.
Titanium is also nonallergenic. This, combined with the fact that it is rust proof makes it great for artificial joints as well as piercings.

24. Chemical and physical properties – So what?
Tungsten is usually used as the filament in lightbulbs because it has the highest melting point of any metal.
It glows red hot when electricity runs through it, and it gives off both heat and light.

25. Chemical and physical properties – So what?
Vanadium is heavier and harder than titanium, so mixing a tiny bit of vanadium with steel can make cheap tools that are still very strong.

26. Chemical and physical properties – So what?
Helium is almost completely nonreactive (inert).
It is lighter than air, so it’s great for floating balloons (or making funny voices.)
When electricity runs through helium, it glows a creamy pale peach color.

27. Chemical and physical properties – So what?
In 1943, all US pennies were made of zinc plated steel because copper was being used in the war. The pennies had to be coated with zinc because steel will rust, but zinc won’t.

28. Chemical and physical properties – So what?
Sulfur smells awful. Rotten eggs, onions, and garlic all have sulfur in them. Stink bombs use sulfur to create a bad smell.
Sulfur is also flammable, and it is one of the 3 main ingredients in gun powder.

29. Chemical and physical properties – So what?
Chromium is famous for its intense luster. Chrome plated tools, jewlery, silverware, or car parts are very popular.

30. Chemical and physical properties – So what?
Most bullets are made of lead because lead is a very dense metal. These bullets are required, by international law, to be coated with a different metal because lead has such a low melting point and is so malleable.

31. Chemical and physical properties – So what?
The most dense elements are Iridium and osmium which have a density of about 22.6 g/cm3

32. Physical Change
A Physical change is a change in a substance that does not change what the substance is.

33. Physical Change - examples
Examples of physical change include:
Change in shape
Change in size
Change in phase
Melting (solid to liquid)
Boiling (liquid to gas)
Evaporation (liquid to gas)
Condensation (gas to liquid)
Freezing (liquid to solid)
Sublimation (solid to gas)
Deposition (gas to solid)

34. Physical Change Physical changes might be caused by: Grinding Cutting
Crushing
Bending
Breaking
Heating/cooling
(change in phase)
squishing

35. Physical Change
Evidence that a physical change has occurred might include:
Change in shape
Change in form
Change in size
Change in phase (This is always a physical change!)
Physical changes are usually reversible

36. Chemical change
A chemical change is a change in which a substance is changed into a different substance. (You’ve changed what it is.)

37. Chemical change Examples of chemical changes include: Burning Rusting
Tarnishing
Decomposing
Polymerization

38. Chemical change
Chemical changes occur when a chemical reaction causes bonds between atoms to break or to form.

39. Chemical change – Chemical reactions
There are 5 types of chemical reactions that cause chemical changes to occur.

40. Chemical change – Chemical reactions
1- Composition reactions
Two things come together to form something new
A + B = AB
2H2 + O2  2H2O

41. Chemical change – Chemical reactions
2- Decomposition reactions
1 thing breaks apart to form 2 or more things.
AB = A + B
2H2O  2H2 + O2

42. Chemical change – Chemical reactions
3- Single replacement reactions
One atom replaces another atom
A + BC = AC + B or A + BC = AB + C
Mg + 2HCl  H2 + MgCl2

43. Chemical change – Chemical reactions
Double replacement reactions
Two chemicals switch places
AX + BY = AY + BX
2KI + Pb(NO3)2  PbI2 + 2KNO3

44. Chemical change – Chemical reactions
Combustion reaction
A substance combines with oxygen and releases energy.
C3H8 (propane) + 5O2  3CO2 + 4H2O

45. Chemical Change: Evidence
Evidence that a chemical change has occurred might include:
A color change
An odor change
Formation of a precipitate (you mix two liquids and make a solid)
Gas is formed (bubbles)
Changes in physical properties.

46. Physical and Chemical change
During a chemical change energy can be released in the form of:
Heat
Light

47. Physical and Chemical change - heat
A chemical reaction that releases energy in the form of heat is called exothermic.
Heat comes OUT
Exo = out
Thermic = heat
It will feel HOT.

48. Physical and Chemical change - heat
A chemical reaction that absorbs energy in the form of heat is called endothermic.
Heat goes IN
Endo = in
Thermic = heat
It will feel COLD

49. I. Law of Conservation of Mass
Although chemical changes occur, mass is neither created nor destroyed in a chemical reaction
Mass of reactants equals mass of products
massreactants = massproducts
A + B  C

50. I. Conservation of Mass GIVEN: WORK: 10.00 g = 9.86 g + moxygen
In an experiment, g of red mercury (II) oxide powder is placed in an open flask and heated until it is converted to liquid mercury and oxygen gas. The liquid mercury has a mass of 9.26 g. What is the mass of the oxygen formed in the reaction?
GIVEN:
Mercury (II) oxide  mercury + oxygen
Mmercury(II) oxide = g
Mmercury = 9.86 g
Moxygen = ?
WORK:
10.00 g = 9.86 g + moxygen
Moxygen = (10.00 g – 9.86 g)
Moxygen = 0.74 g
Mercury (II) oxide  mercury + oxygen
Mmercury(II) oxide = g
Mmercury = 9.26
Moxygen = ?
massreactants = massproducts