1. Matter and Change
Mrs. McGuire
Chemistry

2. State (solid, liquid, gas) Composition
A) Classification of Matter Some Criteria for the Classification of Matter
Properties
State (solid, liquid, gas)
Composition

3. -Depend on amount of matter. Ex: mass, length, and volume
Properties
Intensive
-Do not depend on amount of matter. Ex: color, odor, luster and conductivity
Extensive
-Depend on amount of matter. Ex: mass, length, and volume

4. Intensive and Extensive Properties
Sulfur

5. Physical: observed without changing the composition of the substance.
Properties
Physical: observed without changing the composition of the substance.
Chemical: the ability of a substance to undergo a specific chemical change

6. REGENTS QUESTION
Which statement describes a chemical property of sodium?
(1) Sodium has a melting point of 371 K.
(2) Sodium has a molar mass of 23 grams.
(3) Sodium can conduct electricity in the
liquid phase.
(4) Sodium can combine with chlorine to
produce a salt

7. Examples of Physical Properties
Color, odor, hardness, density, melting point, boiling point, state, solubility.

8. Example: Physical Properties
Substance
State
Color
Melting
Point (C°)
Boiling Point (C°)
Density (g/cm3)
Oxygen O2
Gas
Colorless
-218
-183
0.0014
Mercury Hg
Liquid
Silvery-white
-39
357
13.5
Bromine
Br2
Red-brown -7 59
3.12
Water
H2O
100
1.00
Sodium Chloride
NaCl
Solid
White
801
1413
2.17

9. fixed shape and volume, incompressible Liquid
States of Matter
Solid
fixed shape and volume, incompressible
Liquid
fixed volume, takes the shape of its container
Gas
takes the volume and shape of its container

11. STATES of matter

12. Bromine
Gas (Vapor)
Liquid

13. Change of Phase Condensation gas  liquid Freezing liquid  solid
Deposition gas  solid
Melting solid  liquid
Evaporation liquid  gas
Sublimation solid  gas
Boiling: Evaporation occurring beneath the liquid’s surface.

14. BONUS REGENTS QUESTION
Which physical change is endothermic?
(1) CO2(s) → CO2(g)
(2) CO2(g) → CO2(ℓ)
(3) CO2(ℓ) → CO2(s)
(4) CO2(g) → CO2(s)

15. Chemical Properties and Chemical Changes
Is changing phase a physical or chemical change? ___________________Explain:

16. H2O composition is fixed- compound
Gaseous Phase
Liquid Phase

17. Draw at least five particles to represent the phase of the product.
REGENTS QUESTION
Coal is a fuel consisting primarily of carbon. In an open system, the carbon that burns completely in air produces carbon dioxide and heat. This reaction is represented by the balanced equation below.
C(s) + O2(g) → CO2(g)+ heat
Draw at least five particles to represent the phase of the product.

18. Chemical Properties
The ability of a substance to transform into a new substance (to undergo a chemical change).
Example: Magnesium reacts with oxygen to form magnesium oxide.

19. Magnesium Mg

20. Burning of Magnesium 2Mg+ O2 2MgO

21. REGENTS QUESTION Which term identifies a type of chemical reaction?
(1) decomposition
(2) sublimation
(3) Distillation
(4) vaporization

22. Physical Changes
Physical change: a change in the physical properties of a substance.
Composition does not change.
May be reversible or irreversible.
Examples:
Reversible: Liquid water < -- > solid water
Irreversible: Tearing a piece of paper

23. Chemical Change
A change that produces matter with a different composition than the original matter.
Atoms rearrange themselves into new combinations.

24. Burning of Methane CH4 +2O2 CO2 + 2H2O

25. Burning of Methane CH4 + 2O2 CO2 + 2H2O

26. Recognizing a Chemical Change
energy exchange
production of a gas
color change
formation of a precipitate

27. Formation of a Precipitate
Cu(OH)2
Precipitate

28. The Law of Conservation of Mass (Antoine Lavoisier)
In any chemical or physical change, mass is neither created or destroyed
Mass is CONSTANT

29. Classification of Matter (by composition)

30. Matter that has a uniform and definite composition.
(Pure) Substance
Matter that has a uniform and definite composition.
Elements: organized on a periodic table, unique name, one, two or three letter symbol
Compounds: two or more elements combined chemically

31. REGENTS QUESTION All atoms of uranium have the same (1) mass number
(2) atomic number
(3) number of neutrons plus protons
(4) number of neutrons plus electrons

32. REGENTS QUESTION
Which substance can not be broken down by a chemical change?
(1) ethane
(2) silicon
(3) Propanone
(4) water

33. c) Elements and Compounds
Pure substances
Elements can NOT be decomposed by chemical means, but compounds can.

34. The simplest substances. Can not be separated into simpler substances.
Elements
The simplest substances.
Can not be separated into simpler substances.
Building blocks of all matter.
More than 100 known elements.
Represented by chemical symbols.

35. Chemical Symbols of Elements
System started by Jons Berzelius (Sweden, )
One or two first letters of name of the element.
Many elements names have roots from: Latin, Greek, mythology, geography, names of scientists.

36. Examples: Americium, Am Einsteinium, Es Bromine, Br Helium, He
Lead(Plumbum), Pb
Niobium, Nb
Iron (Ferrum), Fe
Mendelevium, Md

37. Compound
A substance that contains two or more elements chemically combined.
Compounds have different properties from the individual substances.
(Ex: H2O)

38. Example: H2O

40. The law of definite proportions states that a compound is always composed of the same elements in the same proportions.

41. Percent composition

42. If composition is fixed and may not changesubstance
Substance or mixture?
If composition is fixed and may not changesubstance

44. REGENTS QUESTION Which sample of matter is a mixture? (1) Br2(ℓ)
(2) KBr(s)
(3) K(s)
(4) KBr(aq)

45. Uniform composition and properties throughout
Mixture: a physical blend of two or more substances that are not chemically combined.
Homogeneous:
Uniform composition and properties throughout
Heterogeneous two or more sustances are physically combined and retain their original properties

46. A physical blend of two or more substances.
Mixtures
A physical blend of two or more substances.

47. Mixtures
Homogeneous
Heterogeneous

48. Example: Stainless Steel
A homogeneous mixture of:
-Iron (Fe)
-Chromium (Cr)
-Nickel (Ni)

49. Heterogeneous Mixtures
Example:
Oil and vinegar
Non-uniform composition throughout the mixture
Two or more phases.

50. Example: Gaseous Mixture
Elements argon and nitrogen and a compound (water vapor). Choice ?

51. Mixtures can be physically separated.
Note:
Mixtures can be physically separated.
Mixtures exhibit physical properties similar to the components of the mixture.

52. Separation Methods
Use differences in the physical properties of the components of the mixture.

53. Example: Separate iron filings from sulfur using a magnet.

54. Filtration: separates a solid from a liquid in a heterogeneous mixture

55. Distillation: -separate dissolved solids from a liquid -uses boiling and condensation.

56. Distillation of Crude Oil (Refining)
Crude Oil is a mixture of Hydrocarbons

57. BONUS REGENTS QUESTION
Which formula represents a hydrocarbon?
(1) CH3I
(2) CH3CH3
(3) CH3NH2
(4) CH3OH

58. Distillation of Crude Oil

59. REGENTS QUESTION
A mixture consists of sand and an aqueous salt solution. Which procedure can be used to separate the sand, salt, and water from each other?
(1) Evaporate the water, then filter out the salt. (2) Evaporate the water, then filter out the sand.
(3) Filter out the salt, then evaporate the water. (4) Filter out the sand, then evaporate the water.