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Interest Grabber
What’s the Matter?
All of the materials around you are made
up of matter. You are made up of matter,
as are the chair you sit on and the air you
breathe.
1. Give an example of solid matter.
2. Give an example of liquid matter.
3. Give an example of gaseous matter.
4. Is all matter visible?
5. Does all matter take up space?
made of protons (+), neutrons, and
electrons (-)
 element = pure substance consisting of
only one type of atom
 compound = chemical combination of
two or more elements

An Element in the Periodic Table
AN ELEMENT IN THE PERIODIC TABLE
Section 2-1
6
C
Carbon
12.011
6 electrons
6 protons
6 neutrons
electrons = protons =
atomic number
Atomic mass - # electrons =
neutrons
Figure 2-2 Isotopes of Carbon
ISOTOPES
OF CARBON
Section 2-1
Vary in the number of neutrons
Nonradioactive carbon-12
Nonradioactive carbon-13
6 electrons
6 protons
6 neutrons
6 electrons
6 protons
7 neutrons
Radioactive carbon-14
6 electrons
6 protons
8 neutrons

Ionic Bonds  electrons transferred from
one atom to another
 anion = - charge
 cation = + charge

Covalent Bonds  electrons shared by
atoms
 molecule is smallest unit of most
compounds

Van der Waals Forces
 sharing of electrons not always equal
 areas of molecule may have slight
charge that can lead to slight attraction
if in close proximity
 weak but can hold large molecules
together
 geckos

Hydrogen Bonds  see water info
single most abundant compound in most
living things
 greatest solvent on Earth

Polarity
 Water molecule is polar because there is an
uneven distribution of electrons between the
oxygen and hydrogen atoms
 Oxygen has a slight (-) charge; Hydrogen has
slight (+) charge
 like a magnet with 2 poles
Attraction between the hydrogen of one
water and the oxygen of another.
 Allows for cohesion and adhesion
 Because of polarity, hydrogen bonds usually
form between oxygen, fluorine and nitrogen

 not as strong as covalent or ionic bonds

because water is polar it is able to form
multiple hydrogen bonds – accounts for many
of water’s special properties
 expands slightly upon freezing
 ice less dense than water
 Hydrogen bonds allow water to dissolve
many substances – critical to living cells
Cohesion – attraction between molecules
of the same substance
 water is extremely cohesive
 creates surface tension
 Adhesion – attraction between molecules
of different substances
 water will adhere to the walls of a glass
container

ice is less dense than water so it floats
on top
 floating ice insulates the water
underneath and prevents it from
freezing
 allows aquatic organisms that live in
the water to survive during cold
weather

Heat capacity  amount of heat energy
needed to increase temperature
 requires large amount of heat to speed up
molecules [raises temp]
 heat capacity for water is high
 body of water can absorb large amounts of
heat without large temp changes
 What are the benefits to this?

 composed of solute and solvent
solvent – substance in which solute
dissolves
 solute – substance that is dissolved


water and non dissolved material
 movement of water molecules keep
small particles suspended
 blood  water with blood cells and
other undissolved particles
H2O  H+ + OH
pH Scale
pH SCALE
water
Increasingly Basic
Oven cleaner
Increasingly Acidic
Neutral
hydrogen
ion
hydroxide
ion
Bleach
Ammonia solution
Soap
pH scale indicates the
concentration of H+ ions
Sea water
Human blood
Pure water
Milk
Normal
rainfall
Acid rain
Tomato
juice
Lemon juice
Stomach acid
Acid = contain higher
concentrations of H+ ions than
pure water
pH value below 7
Base = lower concentrations of
H+ ions than pure water
pH value above 7

weak acids and bases that react with
strong acids and bases to prevent sudden
changes in pH
 blood pH = 7.4
 changes prevented by buffers such as
bicarbonate and phosphate ions
 buffers play important role in
homeostasis

Organic Compounds
 all contain the element carbon
 study of organic compounds known as
organic chemistry
 4 groups




Carbohydrates
Lipids
Proteins
Nucleic Acids
Figure 2-11 Carbon Compounds
CARBON COMPOUNDS
Section 2-3
STRUCTURAL FORMULAS
Methane
Acetylene
Butadiene
Benzene
Isooctane
composed of carbon, hydrogen and
oxygen
 main source of energy for all living
things
 also used for structural purposes
(cellulose)

 Terminology
monosaccharides
 simple sugars  ex. Glucose, fructose
 C6H12O6
 building blocks of complex carbs
 disaccharides
 double sugars  ex. Sucrose, lactose,
maltose
 C12H22O11
 glucose + fructose = sucrose
glucose + glucose = maltose

 Polysaccharides
complex sugars
 plants store sugar as starch
 animals store sugar as glycogen
 cellulose  starch used for structural
purposes in plants [cell wall]

 Includes
fats, waxes, oils
fats
 solid at room temp, produced by animals
(except fish)
 saturated fats – cause heart disease
 oils
 liquid at room temp, produced by plants
 unsaturated fats – better for you
 a few plant oils are saturated – coconut
oil
 waxes
 plants and animals

stored as energy reserves
 part of biological membranes and
waterproofing
 composed of fatty acid & glycerol
molecules

building blocks of living material
 important in growth, maintenance, &
repair
 help run chemical reactions
 made up of amino acids  20 of them
 amino acids joined by peptide bonds
 dipeptide = 2 amino acids
 polypeptide = many amino acids
 examples of amino acids = valine, lysine,
glycine

 4 Levels
Primary  sequence of amino acids
 Secondary  folding and coiling of the
chain
 Tertiary  three-dimensional
arrangement
 Quaternary  found in proteins with
more than one polypeptide (chain)






most complex biological compounds
DNA  deoxyribonucleic acid
RNA  ribonucleic acid
control heredity
composed of nucleotides which have 3
parts:
 5 carbon sugar
 nitrogen base
 phosphate group
Nucleotide

Monomer = smallest unit into which an
organic compound can be broken
carbohydrates = monosaccharides
 lipids = fatty acids and glycerol
 proteins = amino acids
 nucleic acids = nucleotides

Concept Map
CONCEPT MAP FOR CARBON COMPOUNDS
Section 2-3
Carbon
Compounds
include
Carbohydrates
Lipids
Nucleic acids
Proteins
that consist of
that consist of
that consist of
that consist of
Sugars and
starches
Fats and oils
Nucleotides
Amino Acids
which contain
which contain
Carbon,
hydrogen,
oxygen
Carbon,
hydrogen,
oxygen
which contain
which contain
Carbon,hydrogen,
oxygen, nitrogen,
phosphorus
Carbon,
hydrogen,oxygen,
nitrogen,
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