1. Honors Biology Chapter 2
Chemistry

2. DRY ERASE ATOM ATTITUDE
Everyone gets a dry erase board, dry erase pen, and tissue for erasing.
The teacher will ask you a question about atomic structure, you will write your answer and hold up your board.

3. Are you wondering why we are learning chemistry in biology class?
All of our cells are made of chemical compounds.
All the activities of our bodies work on chemical reactions.
All of our body’s reactions use water.
Such as neurotransmitters affecting neurons

4. MATTER
Anything that occupies space (VOLUME) and has MASS
Is air matter?
Yes

5. Match as energy (capacity to do work) or matter (occupies space and has mass)
Water
Electricity
Air
Helium
Sunlight
Iron
Carbon
Matter
Energy

6. 2.1 ELEMENTS, ATOMS, COMPOUNDS (are matter)

8. YOU NEED TO KNOW
The Names (spelled correctly) and the Symbols (written correctly) on p. 18 (Table 2.1)
“Elements in the Human Body”
25 elements (includes trace elements)
QUIZ on FRIDAY Sept. 27

9. ELEMENTS
Substance that cannot be broken down to other substances by ordinary chemical means (heating, adding an acid…)
YouTube - ?Tom Lehrer's
The Elements" animated??
****ASAP SCIENCE Periodic Table
In Order
OR YouTube - ?The Elements Animation??

10. Where can you find an element?
The Periodic Table of the Elements – see Appendix 2 and get your personal copy

11. ELEMENTS AND SYMBOLS: Ca, H, Li, O, C, Mg
What rules apply to writing the symbols (abbreviations of the elements)?
First letter capital, second letter is lower case
What are the four most common elements in the human body? (see chart)
CHON
What are trace elements?
Less than 0.01% of human body weight

12. Which are elements? Cu C CO N NO WHY? Cu C N only one kind of matter
Gold - Au

13. COMPOUNDS
Substance of two or more different atoms chemically combined in a fixed ratio
EXAMPLES: CO2
H2SO4
H2O CO
How is a compound written differently than an element?
More than one kind of element (more than one capital letter).
NOTE: H2 is not a compound – its an element
(Only one kind of element)
Subscripts (tell how many atoms there are)

14. Formula Formula is the abbreviation for a compound. CO2 H2SO4 H2O
Carbon dioxide sulfuric acid water
What rules seem to apply to writing a formula?
Capital letters for elements
Subscript number behind and just below the line of what element it represents

15. Which are compounds? Na N H2 NO2 H2O Why? NO2 H2O
2 or more different elements chemically joined (2+ diff. capital letters)

16. Which are symbols? Abbreviations for elements
C CO2 Mn CO Ni Why?
C Mn Ni
Only one capital letter

17. What’s the difference?
Co CO co
Symbol formula nothing

18. Which are formulas? Abbreviation for a compound
H2SO Cl H Al Why?
H2SO H20 abbreviations for compounds (2 or more different kinds of elements)

19. Can you figure out the difference between a mixture and a compound?
A mixture is two or more elements (or compounds) NOT chemically joined.
A compound is two or more atoms chemically joined.
Do Worksheet: Elements, Compounds, Mixtures

20. DO WORKSHEET: Elements, Compounds, Mixtures
(back of Atomic Mass and Atomic Number Worksheet)
Work in groups of three, then we’ll compare answers.

21. 2.2 What are trace elements?
Needed in the body in only small amounts
Like mg (milligrams)
WHY IMPORTANT IF WE DON’T NEED SO MUCH?
Minerals act as catalysts (speed up reactions) for many biological reactions

22. Trace Elements Needed by some organisms but only in very small amounts
Like iodine, we need only 0.15 mg per day
A deficiency will cause a goiter

23. Trace Elements Fluorine – in drinking water, toothpaste
(help dental decay)
But too much can cause fluorosis (white chalky build-up)

24. Trace Elements Iron Rich Foods Most important use is to carry
oxygen in the blood

25. 2.3 Atoms and Molecules

26. Atoms are made of protons, neutrons, electrons
Do you know what these particles are?

27. Answers: Do you know what these particles are? Protons Neutrons
Electrons

28. Basic Atomic Structure Youtube (1:57)

29. Atom
Smallest unit of matter that retains the properties of the element Li Na

30. C and N only one in number Which are elements? C N N2
Which shows one atom?
C N N2 H Why?
C and N
only one in number
Which are elements?
C N N2

31. Molecule
Two or more atoms held together by chemical bonds

32. Which are molecules? Co CO CO2 O2 Why?
CO CO O2 two or more atoms (alike or not alike, it doesn’t matter) bonded together

33. Where is each subatomic particle located?
Proton in the
Neutron nucleus
Electron-outside the nucleus
Golden Retrievers Show Atomic Structure Youtube (2:11)

34. What is the charge of each subatomic particle?
Proton Neutron Electron
O _
positive none negative

35. What is the relative size?
Proton neutron electron
1 amu amu ~1/1836 amu
AMU = atomic mass unit = 1/12 CARBON ATOM
(standard)

37. Neutral Atoms (no charge) (as seen on the periodic table)
Mass Number p + n
K Symbol
Atomic Number p
(electrons = number of protons)
Neutral if negative charges = positive )

38. How can you tell the mass number and atomic number?

39. When looking on the periodic table…
Atomic Number
In order
Identify element by its number of protons
Mass Number
A decimal (average of masses of all isotopes of that element)

40. Why is the mass number a decimal? Average of the Isotopes of Carbon
What is the mass number decimal?
12.011
What would you round it to? 12

41. What is the atomic number of?
Silicon fluorine sodium WHY?
Number in succession (not a decimal)
Number of protons

42. What is the mass number of…?
Carbon nitrogen hydrogen
WHY?
Decimal number on periodic table
Not other number in succession
Number of p + n

43. How do you find the number of…?
Protons electrons neutrons
Atomic atomic mass number number number minus atomic no.
(if neutral)

44. How many?
Protons electrons neutrons
Carbon
Chlorine

45. What is the atomic number? Mass Number?
Number of p?
Number of e-?
Number of n?

46. Do Atomic Mass and Atomic Number WORKSHEET
Collaborate with your partner next to you, then we’ll see what’s right.

47. ISOTOPES INTRO Isotopes (Virtual School) (2:51)
Watch the video and list what facts you learned about isotopes.
No, not about the Albuquerque Isotopes

48. Isotope Atoms that differ in number of neutrons
Also differ in mass number(since it is p + n)
But all have the same number of protons

49. Isotope Examples
What are isotopes? (7:56)

50. Which is the most common isotope of Li? (check the periodic table)

51. Why is the Mass Number a Decimal?
Finding the Average Atomic Mass (2:55)
Watch this and find out how…

52. How do you write chemical notation for isotopes?

53. 2.4 Radioactive Isotopes
An isotope that decays spontaneously to emit (give off) particles or energy until it is stable
Here a radioisotope is used to examine a thyroid gland
Radioactive Tracers in Medicine (3:57)

54. Radioactive Decay Examples

55. Uses of Radioisotopes
C-14 dating (can date living things up to 6,000 years old) Carbon Dating (2:00 mins)
Technetium 99 Radioisotope (2:58)
Nuclear Medicine: What to expect (2:46 mins)
Bozeman Biology Radioactive Dating (9 mins)
Carbon-14 Dating (2 mins)
PET SCAN: detect tumors, weak spots in arteries
Highlight parts of the body for diagnosis
Thyroid tumor

56. Uses of Radioisotopes Iodine-131 PIB molecule to
treat thyroid cancer detect Alzheimers
PET scan

57. Negative Effects of Nuclear Radiation
Chernobyl Nuclear Plant Accident

58. Negative Effects of Radon
Radon, a radioactive gas, causes lung cancer
Found in regions containing uranium

59. Chemical Bonds

60. Ion Charged atom Differs in number of electrons 39 Same mass number
K means lost one electron
Same atomic number

61. ION Charged atom Na+ (has lost one electron)
O-2 (has gained two electrons)
Shown with superscript +/- and number on upper right
(can omit number if a “1”)
What's and Ion? Youtube (6:52)

62. Ions form by gaining or losing electrons

63. O-2 has gained two electrons
Na has lost an e- so it is Na+1

64. Cation Positive ion Na+ Mg+2 Lost electrons Negative ion Cl- O-2
Anion
Positive ion
Na+
Mg+2
Lost electrons
Negative ion
Cl-
O-2
gained electrons

65. +1 If one electron is… Lost what charge will the ion have? 11p+ 11 e-

66. Which are ions? Cl O-2 Na+1 N2 Why? O-2 Na+1
Charged atoms (lost or gained electrons)
show charges as superscripts

67. Valence Electrons Outer shell electrons
Determines the bonding capacity of an atom

68. How do electrons arrange themselves in an atom…
In the outer electron shells (energy levels)?
They are full with 2, 8, 8
Fill inner shell first,
then go to next shell out
(Outermost shell has the greatest energy)
Can you see any pattern how
the e- arrange themselves?

69. Get kinda complicated beyond 2,8,8…so that’s all we’ll do for now!

71. Which electrons determine…
The chemical properties of the atom?
Outermost shell

72. If one electron is gained…
What charge will the ion have? -1

73. -2 +2 If 2 electrons are lost… What charge will the ion have?
If two electrons are gained… What charge will the ion have? -2

74. Filled outer e- shells
How many e- fill the first shell (nearest the nucleus)?
How many e- fill the next two shells?
nucleus

75. Gain 1 e- or lose 7 e-?
If gains 1 e-, then it becomes -1

76. Gain 7 e- or lose 1 e-?
If loses 1 e-, the it becomes +1.

77. Gain or Lose ?
If it could as easily lose or gain e-, then it will probably share them. It will form a covalent bond.
Tutorial 2.1 Chemical Bond Formation

78. Fill in the chart of e- Element Number of e- First shell Second Third
Shell Shell
carbon 6
lithium 3
Sodium 11
Oxygen 16

79. Fill in the chart of e- Element Number of e- First shell Second Third
Shell Shell
carbon 6 2 4
lithium 3 1
Sodium 11
Oxygen 8

80. How are ion charges determined?
Cation = positive (+) ion
Anion = negative (-) ion

81. How are ion charges determined?
If lose 1 e- = +1 charge
If gain 1 e- = -1 charge
If lose 2 e- = +2 charge
If gain 2 e- = -2 charge

82. Periodic Table Hint:
You can tell how many electrons are in an atom’s outermost shell by just looking at its position on the periodic table!!!!!

83. Note any pattern of valence electrons (outer shell) as they appear in the periodic table?

84. e- in outer shells +1 +2 Ion formed e- in outer shell share -3 -2 -1 0
+1 +2
Ion formed
share
e- in outer shells 8
e- in outer shell H
Full outer e- shells

85. How many electrons in each shell? (atomic number is given)
Carbon oxygen fluorine sodium
2, , , ,8,1

86. How many valence electrons
How many valence electrons? Will these atoms lose or gain e- and how many?

87. How many valence electrons
How many valence electrons? Will these atoms lose or gain e- and how many?
Lose lose O lose share gain lose 1
H He Li C N Na+

88. Now let’s do the Drawing Atoms Worksheet (and next 4 slides)
How the electrons fill their shells (link)
1st shell – 1 pair
2nd shell – e- space far apart, singles, then pair
3rd shell – e- space far apart, singles, then pair

90. Bohr Diagram Let’s do carbon (6 electrons)
1. Draw a nucleus.
2. Draw the number of rings needed.
3. Start in the first shell- only 2 e-, paired (put next to each other)
Get worksheet C

91. 1 2 4 3

92. 1 5 2 4 6 3

93. Bohr model electron filling order2

94. Are these correct Bohr models?

95. Are these correct Bohr models?
What errors are at the ?

96. Now do on the Atomic Structure Worksheet

97. See the trend of how electrons fill the valence shells
Lewis dot structures
Octet Rule – electrons fill a shell until it’s full with 8 electrons
Atoms are most stable with a filled outer electron shell

98. What do we call the forces that…
Hold atoms together in a molecule?
Chemical bonds
…not to be confused with James Bond

99. To have filled outer electron shells!
Why do atoms bond?
To have filled outer electron shells!
Atom Heaven
ATOM

100. What is a chemical bond?
Attraction between two or more atoms YouTube - ?Ionic and covalent bonding animation??

101. Get Bonding Handouts Electronegativities Intermolecular Forces
Bonding Reference Sheet

102. Types of Bonds Intramolecular Intermolecular Within the molecule
-Ionic
-Covalent
Polar
Nonpolar
Between different molecules
Van der Waals
London forces
Dipoles
Hydrogen Bonds

103. Ionic Bonding Covalent share electrons transfer of electrons
(lose or gain)

104. IONIC BOND lose one or more electrons become (+)
gain one or more electrons become (-)
The (+) and (-) ions formed now attract each other and form an ionic bond.

106. Covalent Bonds Polar Covalent Unequal sharing of e- Nonpolar Covalent

107. Covalent Bonds Click HERE: Polar Covalent Bonding (3 animations)
Electrons are shared
Usually if near the same number of e- in outer shells

108. Covalent bonding can be shown as:
Bohr model
Electron-dot
Structural Formula

109. How can covalent bonds be written?
Single bond double bond triple bond
C-C C=C C=C
C:C C::C C:::C
2 e e e-

110. Writing Bonds Each “ –” is equal to “ : “ or “two electrons”
Single C – C or C:C
Double C = C or C::C
Triple or C:::C
C≡C

112. Different Ways to Represent Four Common Molecules
butane

113. Making ionic bond in NaCl
YouTube - ?Ionic and covalent bonding example??
YouTube - ?Reaction of Sodium & Chlorine (with subtitles)??

114. SALT = Synonym for an ionic compound Not just NaCl Sodium chloride
Copper Sulfate
Iron Sulfide

115. LET’S REVIEW: Which atoms combine…
with other atoms?
Ones that do not have filled outer electron shells

116. TO HAVE FILLED OUTER ELECTRON SHELLS
REVIEW: What is the driving force to make atoms join with other atoms to form compounds?
TO HAVE FILLED OUTER ELECTRON SHELLS

117. REVIEW: How does an atom…
Get a filled outer electron shell?
Gaining, losing, or sharing electrons

119. What do you notice about the ion charge and the subscripts?

120. Do the Flip-Flop
So you can cancel out the (+) and (-)

121. If there is only one atom, you do not need to write a “1”
You can reduce the subscripts if they are the same:
Fe O Fe2O2
reduce to FeO

122. Get Electronegativities handout
Electronegativity
Get Electronegativities handout

123. Electronegativity Tendency of an atom to attract
electrons towards itself and thus
the tendency to form negative ions.

124. Electronegativity NONPOLAR – equal sharing of electrons
The more electronegative atom pulls shared electrons toward its nucleus.
NONPOLAR – equal sharing of electrons
POLAR – unequal sharing
of electrons

125. H = 2.1 O=3.5 C=2.5 Electronegativities H-H = 0.0 bond pure covalent
O-H bond = 1.4 polar
( )
covalent
NaCl = 2.1 ionic

126. Molecule
A group of two or more atoms held together by covalent bonds

127. What’s the difference between Intramolecular and Intermolecular Forces?

128. What’s the difference?
Intermolecular attractions are between one molecule and a neighboring molecule
(Van der Waals, hydrogen bonds)
USUALLY WEAKER
Intramolecular attractions are the forces which hold an individual molecule together (for example, the covalent bonds or ionic bonds).
USUALLY STRONG

129. WHAT IS THE STRENGTH COMPARISON?
STRONGEST BOND
WEAKEST BOND
Covalent
Ionic
Hydrogen
Van der Waals
(dipole-dipole
London forces)
intramolecular

130. INTERMOLECULAR FORCES
A. H-bonds (H to F, O, or N)
B. van der Waals- temporary “dispersion” London (nonpolar) and dipole-dipole forces (polar)
C. Disulfide bridges (-S-S-)
Intermolecular Forces Youtube (9:11-if ya got time)

131. Intermolecular Forces video and worksheet
What three types of intermolecular forces are there?
What does dipole mean? Why do those molecules attract each other?
London forces are in molecules that are not dipoles. What do they do to their e- to cause an attraction?
What three possible atoms can make a hydrogen bond with hydrogen?
List the forces in order of strength.

132. Hydrogen Bonds: Intermolecular between H and F, O, or N

133. Where Might you find Hydrogen Bonds?
In Water – between O- and H+
In DNA – between bases

134. Intramolecular: Van der Waals
Van der Waals on Gecko Feet (8:22)
Is the sum of the attractive forces between molecules (but not H-bonds or covalent bonds)

135. van der Waals Temporary dispersion of electrons make temporary charges
Van der Waals Dispersion Forces
Temporary dispersion of electrons make temporary charges

136. Where might you find van der Waals?
crystal structures (e. g. the shapes of snowflakes),
DNA shape

137. Intramolecular: (Van der Waal type) Dipole-dipole
exists between neutral polar molecules only when they are close together
Dipole Forces Bozeman youtube (7:32)
Temporary shift of the electrons to make a partial + and a partial - end

138. Weakest van der Waals: London Dispersion Forces
Temporary polarity between nonpolar atoms or molecules
All molecules have them at some time
Bozeman London Dispersion Forces (5:02)

139. London Dispersion Force London Dispersion Force Animation

140. Disulfide Bonds: Protein Tertiary Structure
Disulfide Bond in Tertiary Protein

141. Disulfide Bonds
formed between the side chains of cysteine in a protein SH) to form a disulfide bond (S-S)
(Will learn about this in Chapter 3)

142. THEME OF EMERGENT PROPERTIES
New properties that arise with each step upward in the hierarchy or life, owing to the arrangement and interactions of parts as complexity increases.
WHOLE IS GREATER THAN THE PARTS

143. How is the emergent property idea apply to a compound and atoms?
HINT:

144. 2.9 Chemical Reactions
The making and breaking of chemical bonds, leading to changes in the composition of matter.

145. Chemical Reactions Reactants on the left of the arrow
Products on the right of the arrow
IDENTIFY:
2Mg(s)  +  O2(g)  →    2MgO(s)
MgO(s)  +   H2O(l)  →    Mg(OH)2(s)
N2(g)  +  3H2(g)  →    2NH3(g)

146. Same number of each element on left side as on the right side
CH4 (g) + 2O2 (g) CO2 (g) + 2H2O (g)
Reactants
Products
C = 1
H = 4
O = 4

147. Signs of a Chemical Reaction
Precipitate forms
Color Change
Gas Forms
Temperature change

148. Chemical Reaction Videos
Na and Cl Chemical Rx (52 secs.)
Genie in a Bottle Reaction - Steve Spangler (3:36)
Weirdest Chem. Rx in the World (2:52) Mercury(II) thiocyanate Hg(SCN)2
The Naked Scientists Videos (MP3)

149. Chemical Reaction Example
An iron bar rusts. The iron reacts with oxygen in the air to make rust. 4 Fe + 3 O2 2 Fe2O3