Transcript Study Sheet for Chapter 2 Honors Biology

Study Sheet for Chapter 2
Honors Biology
EXTENDED RESPONSE TIPS:
• EXAMPLE:
• Surface tension caused by the pulling in of Hbonds of the water molecules. This creates a
“film” on the surface of the water.
• This allows small insects to walk on the
surface of water.
#1
Atom = 1 unit – smallest unit of
an element
Molecule = 2 or more atoms
chemically bonded (can be same
or different)
• Symbol = abbreviation of
an element
• Formula = abbreviation of a
compound
• Element = 1 kind of
substance that cannot be
broken down by chemical
means – listed on Periodic
table
• Compound = 2 or more
different elements bonded
together chemically
#2
• 59
• Co
• 27
•
•
•
•
•
Mass number = 59
Atomic number = 27
Number of protons = 27
Number of electrons = 27
Number of neutrons = 32
#3
• Trace elements
• Appear in very small amounts
• Milligrams (mg)
#4
• Radioactive isotope
• Breaks down spontaneously
• (gives off energy and particles, can be
detected on a PET scan)
• Break down to their more stable form
• EX: C-14 to C-12
#5
• Why do atoms join to form
compounds?
• TO FILL THEIR OUTER ELECTRON SHELL
#6
• IONS and ISOTOPES
• IONS = differ in the number of electrons
(charged atoms)
• ISOTOPES = differ in the number of neutrons
(different mass numbers)
#7
• Electrons in covalent and ionic
bonds
• COVALENT = electrons are shared
• IONIC = electrons are transferred
(lost/gained)
#8
• Solute and solvent and solution
Water = solvent –
does the dissolving
(larger amount)
Sugar = solute –
being dissolved
Both = solution
#9
• H-bonding
• When water reaches 4oC and below H-bonds
form an open lattice (less dense) in ice
• For surface tension, H-bonds pull the water
molecules inward to form a “film”
#10
• IN ORDER (strongest to weakest):
• COVALENT
IONIC
H-bonding
Van der Waals
#11
• Buffers
• Minimize the change in pH by
adding extra H+ and OH• buffer animation
pH of blood = 7.4
#12
• ACIDS put
H+ ions into solution
(H+ donors)
• BASES put OH- ions into solution
(OH- donors)
#13
• Water has high heat of
vaporization (slow to heat and
also slow to cool)
• So the coastal area temperatures
would change less rapidly than
inland areas
#14
ACIDS
BASES
• Strong 1-3
• Weak 4-6
• Strong 11-14
• Weak 8-10
• pH 3 = [H+] 10-3
• pH 4 is 100 X’s the
H+ ions than pH 6
• pH 11 = 10-11
• pH 6 is 1000 X’s more
H+ ions than pH 9
#15
• Electrons fill
• 2
• 8
• 8
e- fill inner shells first
#16
• ACID PRECIPITATION
• pH lower than 5.2
#17
• COVALENT BONDS – electrons are shared
How can they be written?
• Single bond
•
•
•
C-C
C:C
2 e-
double bond
C=C
C::C
4 e-
triple bond
C=C
C:::C
6 e-
#18
• H+ ions surround Cl• OH- ions surround Na+
#19
• REACTANTS
• Left of arrow
PRODUCTS
right of arrow
#20
+1 +2 Ion formed
share
-3 -2 -1 0
e- in outer shells
H
8
e- in outer shell
Full outer eshells
#20 KNOW
• Elements that are located in the same
column behave more alike chemically
#21
• Polar Covalent = unequal
sharing of e• Nonpolar Covalent = equal
sharing of e-
#22
• Bohr Model
#23
H-H
O-H
NaCl
#24
• UNIQUE PROPERTIES OF
WATER
• 1. H-bonding
• 2. Polarity
#25
•C
H
O
N
• Trace element in mg
#25
trace elements in mg (small amounts)
• Fe
•
Used by RBC to carry oxygen in hemoglobin
• I
•
used to prevent blindness and have proper
use of thyroid
• F
•
used to prevent tooth decay
•
#26
• Elements have different numbers
of protons
• Elements have different numbers
of electrons (form different ions
and different bonds)
#26
• Same column have same outer shell (valence)
electrons
+1 +2 Ion formed
share
-3 -2 -1 0
e- in outer shells
H
8
e- in outer shell
Full outer eshells
#27
• ISOTOPES OF AN ELEMENT
• Same number of protons (same atomic
number)
• Different number of neutrons (different mass
number)
#28
•
•
•
•
Valence electrons (fill inner shell first)
2
8
Fill in the chart of e8
Element
Number First shell Second Third
of ecarbon
6
2
Shell
4
lithium
3
2
1
Sodium
11
2
8
Oxygen
8
2
6
Shell
1
#29
• If atomic number 8
• Can form two more bonds
How many e- do
you need to fill the
outer shell= number
of bonds
to form
#30
• BOTH INTERMOLECULAR
• Van der Waals = are momentary
very weak forces of attraction
between nonpolar molecules resulting
from uneven electron distributions
(EX: gecko hairs on feet and glass)
• H-bonding = forces between H and F, O, or N
#31
• Cations = (+) ions
• Ca +2
• Anions = (-) ions
• F-
#32
You need to break the H-bonds
to vaporize (form a gas)- takes
extra time
You need to form H-bonds to
form ice – takes extra time
#33
•
pH
[H+]
[OH-]
[H+] X [OH-]
•
•
•
•
•
•
•
•
•
•
•
•
•
•
0
1
2
3
4
5
6
7
8
9
10
11
12
13
1 X 10-0
1 X 10-1
1 X 10-2
1 X 10-3
1 X 10-4
1 X 10-5
1 X 10-6
1 X 10-7
1 X 10-8
1 X 10-9
1 X 10-10
1 X 10-11
1 X 10-12
1 X 10-13
1 X 10-14
1 X 10-13
1 X 10-12
1 X 10-11
1 X 10-10
1 X 10-9
1 X 10-8
1 X 10-7
1 X 10-6
1 X 10-5
1 X 10-4
1 X 10-3
1 X 10-2
1 X 10-1
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
1 X 10-14
•
14
1 X 10-14
1 X 10-0
1
X 10-14
acid
neutral
base
Determine the pH
• [H+] [OH-] =
-14
10
•If [H+] =
= pH 4
-10
•[OH-] = 10
-4
10
#34
• Mg-2
• K+
• Ca+2
ClI-
P-3
#35
• REVIEW YOUR ELEMENTS AND
SYMBOLS:
• Ca = calcium
• C = carbon
• Co = cobalt
#36
•
•
•
•
•
INTERMOLECULAR FORCES
Holding ionic compounds
Holding nonpolar molecules
Water to water
Polar molecules (No H)
IONIC
Van der Waals
H-bonds
Van der Waals
#37
• INTRAMOLECULAR FORCES
• A. cations and anions
IONIC
• B. unequal sharing of ePOLAR COVALENT
• C. Equal sharing of e- NONPOLAR COVALENT
D. When e- are transferred
IONIC