1. EARTH CHEMISTRY Matter, Elements, Compounds and Molecules

2. MATTER Anything that takes up space and has mass
All matter has two types of properties—physical and chemical

3. PHYSICAL PROPERTIES OF MATTER
Characteristics that can be observed without changing substances’ composition EX: density, color, hardness, freezing point, boiling point

4. CHEMICAL PROPERTIES OF MATTER
Characteristics that describe how two substances react produce new substances Rusting, burning, reaction with acid or base

5. Take a few moments to fill out the Physical VS Chemical Properties worksheet

6. What are elements?
Elements are pure substances.
This is because they cannot be broken down into simpler substances.
They cannot be made by combining other substances.

7. How many elements?
There are 117 known elements.
92 of the elements can be found in the Earth’s rocks, soil, air and water.
The remainder have been made by nuclear scientists.

8. Atoms and Elements
If you could look at the atoms in a chemical element you would see that they are all the same type.
For example: If you had a sample of Hydrogen, you would see that all of the atoms looked exactly the same.

9. Element Symbols
Each element in the periodic table is represented by a symbol of one or two letters.
These letters (symbols) come from the English, Latin or Greek name for the element.
The first letter is always a CAPITAL and the second letter (if there is one) is always lower case.

10. The elements are organized and presented in the Periodic Table.
The Periodic Table displays the following information about an element:
Symbol
Name
Atomic number
Atomic weight (not always)

11. Parts of Elements on the Periodic Table
Atomic number
Element symbol
Element Name
Atomic
mass

12. Now lets complete an Element Diagram (as it appears on the periodic table) and start the Element Symbols worksheet

14. What are the following elements?Cu Hg Li W Pb
What are the symbols of the elements?
Gold
Platinum
Silver
Xenon
Einsteinium

15. Bill Nye “Atoms” video

16. Work on completing Periodic Table Parts

17. ELEMENTS THAT MAKE UP CONTINENTAL CRUST

18. Watch movie on Safari called Atomic Structure and The Periodic Table

19. Question…
How can only 92 naturally occurring chemical elements form millions of different types of materials on Earth and in space?

20. Compounds

21. What are compounds?
Compounds are formed when two or more different elements chemically combine.
This process is called a chemical reaction.
The new compound formed has different properties from the original elements.

22. +  Compound: Water Hydrogen Oxygen Water
Water forms through the following reaction: + 
Hydrogen
Oxygen
Water
Element
Element
Compound

23. H2O More about compounds
Compounds always have the same ratio of elements. For example: Water always contains two atoms of hydrogen to one atom of oxygen. For this reason, water has the chemical formula:
H2O

24. Compound: Water
H2O
2 atoms of Hydrogen
1 atom of Oxygen

26. Watch “Properties of Compounds” on Safari

27. How do elements and compounds exist?
Some chemical elements, such as gold, mercury, helium and neon are found in nature as single atoms. Others such as hydrogen, oxygen and nitrogen can be found with more than one atom (the same type of atom) joined together.

28. Molecules
When two or more atoms join together (the same or different atoms) a molecule is formed. The atoms are tightly joined. These bonds between atoms in a molecule are called chemical bonds. These chemical bonds cannot be easily broken.

29. More about molecules
Molecules that are elements: Atoms are the same compounds: Atoms are different.

30. ATOMS Atoms are the building blocks of matter
~ 1 million lined up side by side = thickness of 1 piece of paper
Atoms contain subatomic particles:
protons (+ charge)
neutrons (neutral)
electrons (- charge)

31. Subatomic Particle Jokes …

34. Here’s an idea of the mass of these particles!!!

35. ATOMIC STRUCTURE
Protons have a positive charge and neutrons have a neutral charge
Protons and Neutrons are located in the nucleus, which ends up with a positive charge due to the protons
Electron cloud —space around nucleus containing electrons

36.                                                           
(Hydrogen Atom)

37. ATOMIC NUMBER
Number of protons in the nucleus—found as upper # in box There are equal #s of protons and electrons in an atom, therefore, this is also the number of electrons Elements are ordered on the periodic table in order of their atomic number

38. How many PROTONS are there in…
Hydrogen?
Silicon?
Lead?
Barium?

39. How many ELECTRONS are there in…
Fluorine?
Carbon?
Sodium?
Copper?

40. MASS NUMBER Sum of # of protons & neutrons is mass number
If you know the number of protons (atomic number) and number of neutrons, you can determine the mass number
This is close to the atomic mass--# at the bottom of the box

41. Mass number = 73, electrons = 32
Determine the MASS NUMBER and element names
Protons = 6, neutrons = 6,
Mass # =
Protons = 9, neutrons = 10,
Determine the number of NEUTRONs & the element name
Mass number = 14, protons = 7,
Neutrons =
Mass number = 73, electrons = 32

42. Work on “Using the Periodic Table” …skip #s 5, 6, 9 and 10
Work on “Using the Periodic Table” …skip #s 5, 6, 9 and 10. We will do them later.

43. Diagramming Atoms
A diagram of an atom is just a simple drawing of the atom’s structure
First, determine how many protons, neutrons and electrons the atom has.
Then, diagram it using:
a circle w/ a plus sign for protons
circle w/ a minus sign for electrons
a blank circle for neutrons.
Make sure these are located in the correct places!

44. Diagramming Atoms Lithium, Mass # = 7
Protons = 3, Electrons = 3, Neutrons = 4 - - + + + -

45. Diagramming Atoms Carbon, Mass # = 12
Protons = 6, Electrons = 6, Neutrons = 6 - - + - + + + + - + - -

46. Diagramming Atoms Boron, Mass # = 11
Protons = 5, Electrons = 5, Neutrons = 6 - - + + + + + - - -

47. Diagramming Atoms Practice Tomorrow, we begin building our atom models!

48. Sum it up so far…
Definition: Compounds are formed when two or more different elements chemically combine. A molecule is the smallest physical unit of a substance that can exist independently, consisting of one or more atoms held together by chemical forces Chemical formula tells what elements and how many of each atom make up the compound

49. H2O—2 hydrogen atom, 1 oxygen atoms NaCl—1 sodium, 1 chlorine CH4
H2O—2 hydrogen atom, 1 oxygen atoms NaCl—1 sodium, 1 chlorine CH4??? ______________ NO2??? ______________ H2SO4??? ______________

50. CHEMICAL EQUATIONS
Chemical Equations: show how elements and compounds combine in a reaction to form new compounds CH4 + 2O2  CO2 + 2H2O Reactants on left, products on right of the arrow

51. BALANCING
Chemical equations must be balanced—this means an equal number of each atom on both sides of the arrow—use coefficients (#s in front of the compound of element)

52. IONS
Ion = an atom that has an electric charge by losing or gaining one or more electrons. Charges show if the atom has gained or lost an electron: —positive (cation) means electrons lost, - —negative (anion) means electrons gained Na+--sodium with 1 less electron Cl---chlorine with 1 extra electron

53. Anions VS Cations
Cation--An atom or a molecule which is positively charged, i.e. has more protons than electrons. Metals.
Ex: sodium (Na+), Iron (Fe2+), and Lead (Pb2+)
Anion--An atom or a molecule which is negatively charged, i.e. has more electrons than protons. Non-metals
Ex: iodide (I-), nitride (N3-) and hydride (H-)

54. Determine how many extra/less electrons the following atoms have: Al3+ = _______________cation or anion? I- ___________________cation or anion? OH- _________________cation or anion?

55. CHEMICAL BONDS These are forces that hold atoms together
Formed by sharing or transferring electrons between atoms

56. TYPES OF BONDS
Ionic bonds —forms between a metal and nonmetal—electrons transferred
Covalent bonds —forms between two nonmetals—electrons shared

57. GAS/
NONMETAL
GASES
NONMETALS
METALS

58. Are these ionic or covalent compounds?
CO2 Covalent—both are nonmetals LiBr Ionic—Li is metal, Br is nonmetal NaCl Ionic—Na is metal, Cl is nonmetal PCl3

59. Complete #s 5, 6, 9, and 10 on your “Using the Periodic Table” worksheet from last week Complete the Ionic versus Covalent bonds practice

60. MIXTURES
A mixture is a substance consisting of two or more substances that have been combined without chemical bonding taking place Heterogenous mixture —two or more substances are not evenly distributed Homogenous mixture —two or more substances evenly distributed (aka solution)

61. Fruit Salad… Heterogeneous or Homogeneous?

62. Fruit Salad is Heterogeneous… WHY. 1
Fruit Salad is Heterogeneous… WHY? 1. Two or more ingredients are visible in the mixture. 2. The ingredients can be easily separated. 3. The mixture is not the same or is different throughout its container.

63. Kool Aid… Heterogeneous or Homogeneous?

64. Kool Aid is Homogeneous… WHY. 1
Kool Aid is Homogeneous… WHY? 1. The ingredients blended together to create the same mixture. 2. The mixture was one color. 3. Only one ingredient can be seen. 4. The mixture is the same.

65. Paint… Heterogeneous or Homogeneous?

66. Paint is Homogeneous… WHY. 1
Paint is Homogeneous… WHY? 1. The ingredients blended together to create the same mixture. 2. The mixture was one color. 3. Only one ingredient can be seen. 4. The mixture is the same.

67. Oil and Water… Heterogeneous or Homogeneous?

68. Oil and water is Heterogeneous… WHY. 1
Oil and water is Heterogeneous… WHY? 1. Two or more ingredients are visible in the mixture. 2. The ingredients can be easily separated. 3. The mixture is not the same or is different throughout its container.

69. Heterogeneous VS Homogeneous Practice