Atoms:
Basic building block of
matter.
Made up of three subatomic particles:
Protons
+
in the nucleus
Neutrons
neutral
in the nucleus
Electrons
--electron shell
Elements:
Substance made up of all
one type of atom.
Six most common elements
found in living organisms:
C, H, N, O, P, S
hyperlink
Molecules/compounds:
Two or more atoms bonded
together.
Carbohydrates
Lipids
Proteins
Nucleic Acids
Water
C, H, N, O, P, S
-These six elements make
up almost all of the cells, tissues and
organs of all living organism .
-These six elements and the
compounds they form must be
recycled continuously through our
biosphere.
Global Biogeochemical Cycles
Bio=
living/biotic factors
geo=
Geological/nonliving/abiotic
factors
All living organisms require a variety of
nutrients:
Examples:
Carbon dioxide and
water are needed for
Photosynthesis
Sugar, Oxygen and water are need for
cellular respiration.
Inorganic compounds:
Do not contain carbon
Can not be decomposed
Can be recycled
Examples:
Sand, glass, styrofoam
Soil, rocks, metals and
water
Organic Compounds:
Contain carbon
Are decomposed or broken down
and whose nutrients are returned to
the biosphere.
Examples:
Anything living or once living
Dead plants and animals
Proteins, lipids, carbs and
nucleic acids
-is classified as being inorganic because…..
-does not contain carbon
-can not be decomposed
-must be recycled through the environment
through a biogeochemical cycle known as the
water cycle or hydrological cycle.
Water covers most of our planet.
It can be found in oceans, lakes, and
ponds, and in the ground itself.
The water cycle has no beginning or
end.
The water cycle collects, purifies and distributes
the earth’s supply of water.
Important terms:
Evaporation:
to change from a liquid into a gas or
vapor
-Condensation:
to change from a gas into a liquid
-Precipitation:
rain, snow ,sleet, etc….
-Transpiration:
release of water out of a plant.
Runoff:
Rainfall not absorbed by the soil.
Aquifer:
underground bed or layer yielding ground
water for wells and springs
Groundwater:
the water beneath the surface of the
ground, consisting largely of surface water that
has seeped down, the source of water in springs
and wells.
What do you already know
about this important life
sustaining molecule?
1. Made up of two
hydrogen atoms bonded
to one oxygen atom.
2. Atoms
bond to form
an angular
molecule
3. Water is classified as a
polar molecule.
+
Polar because
like the Earth or
a bar magnet it
has a partial
positive and a
partial negative
end.
One of the most important
rules in biology is that:
Opposites attract:
Therefore, one molecule of water’s
positive end is attracted to another
molecule of water’s negative end
giving water many unique
properties.
-
+
-
+
-1. Is an inorganic molecule
-Contains no carbon
-2. Made up of two hydrogen atoms
and one oxygen
3. -forms an angular molecule
4. - Is a POLAR MOLECULE
-has a + and a – end
-5. Covers 75% of the Earth’s surface
-6. Makes up 70% to 80% of a living
organism
+
7. -Occurs in three phases
-Solid
-molecules have a small
amount of energy
-a little movement (just vibrating)
-Liquid
-molecules gain some energy
and some movement
-Gas
-molecules gain a lot of energy
and a lot of rapid movement (enough
to escape the surface )
PHASE DIAGRAM OF WATER
Experiment #1:
500g
-------= 2 g/cm3
250 cm3
What is density?
-mass / volume
Density of water?
10g / 10 ml = 1 g/ml
500 g
--------= 0.2g/cm3
2500 cm3
Experiment #2:
Water
Alcohol
Density: Mass/Volume
Water in it’s solid form is less
dense than its liquid form.
But why?
Again, WHY ?
When frozen, the water
molecules slow down and due
to their polarity they will line
themselves up + to – end thus
taking up more volume and
lowering it’s density.
.
O
H
+
H
H
H
-
H
O
H
+
Solid
O
H
H
Liquid
O
Experiment #3:
What is cohesion?
-waters
attraction to other
water molecules
Cohesion: the attraction between like
molecules. (one water molecule to
another water molecule.
- Due to the fact that water is a polar
molecule and opposites attract.
What is adhesion?
-waters attraction to
other types of molecules
(like the paper)
What is surface tension?
Experiment #5:
A property of liquid
surfaces that causes the
surface layer to behave like
a thin elastic 'skin'.
Molecules in a liquid have
attractive forces that hold
them together.
Molecules on the surface
are attracted to molecules
from all sides and below,
but not from above. ...
Experiment #6:
Why does this occur?
Adhesion is the tendency of
certain dissimilar molecules to
cling together due to attractive
forces.
Water forms a concaved
meniscus.
The water molecules are
attracted to the sides of the
glass container.
Adhesion and
cohesion are the
two properties that
allows water to
move up a plant
against the pull of
gravity.
Experiment #7:
Demo of salt
dissolving
In water.
Dissolves: The molecules of one
substance are picked up and evenly
distributed and surrounded by
another type of molecule.
Experiment #8:
- 2 or more substances combined
but not chemically.
-each substance retains it’s own
properties.
-each substance can be separated
from the other.
Examples???????
- Suspensions
- Solutions
Example: Oil and water
A substance is
mixed with water
and the 2
substances
separate.
The less dense
substance is
“suspended
above” the more
dense substance.
One substance dissolves into another
substance.
Examples:
Kool aid
Salt water
Parts of a solution:
Solvent:
Substance doing the
dissolving. (water)
Solute:
Substance being dissolved.
(salt)
Solution:
Created when the solute
DISSOLVES in the solvent.
(salt water)
Water is known as the Universal Solvent.
-dissolves more substances than any other
solvent including all items that need to be
dissolved in living organisms.
Aqueous solution:
water is the solvent
Saline solution:
salt is the solute
Tincture:
Alcohol is the solvent
Acids, Bases
and Neutral

HCl is Hydrogen Chloride
› H is +1 and Cl is – 1 therefore it is neutral
› Not dangerous to us and our tissues
› When HCl is dissolved into water, the H and
Cl ions separate.

HCl is now known as Hydrochloric Acid
› It is now very dangerous to us and our tissues
NaOH is Sodium Hydroxide
Na is +1 and OH is – 1 therefore it is neutral
Not dangerous to us
When NaOH is dissolved into water, the Na and
OH ions separate.
NaOH, sodium hydroxide is now very
dangerous to us and our tissues
A substance that release no +H
or –OH ions when dissolved in
water
OR
A substance that releases and
equal amount of both the +H
and the – OH ions and they
cancel each other out.
-measures the strength and
weaknesses of an acid (%H+) and
of bases (%OH-)
-based on a scale of 0 to 14
pH and common substances:
When an acid and a base of equal
strength are mixed and cancel
each other out creating a neutral
substance.
HCl + NaOH ---- NaCl + HOH
Strong
acid
Strong
base
neutral
no H or OH
neutral
H = OH
A substance which guards
against shifts in the pH level.
Our blood is an example of a buffer.
Blood uses extra H+ and OH- ions
substances to help resist pH changes in
our body.
-special chemicals that can show
whether a substance is an acid, a base or
is neutral.
-Two type of indicators:
-pH paper: Used to determine the
strength or weakness of an acid or a
base.
Litmus Paper:
-Two types of litmus paper.
-RED
and
BLUE
Red Litmus Paper
Blue Litmus Paper
- stays red when H+
ions are present.
-turns blue when OHIons are present.
- turns red when H+
ions are present.
-stays blue when OHIons are present.
Item
1. Benedict’s
solution
Color Change
Does the RED litmus
paper
change to blue?
yes
no
Color Change
Does the BLUE
litmus paper
change to red?
yes
no
2. Acetamine
yes
no
yes
no
3. Salt water
yes
no
yes
no
Result of Test
acid, base or neutral