Just a few elements,
(usually bonded with other elements in compounds),
make up most the
matter on Earth.
75 % of Earth is covered by….
saltwater.
Saltwater is a mixture of two compounds.
Water = H2O
Salt = NaCl
Based on this…what are the two most
common elements in our oceans?
Decode the compound formulas –
Water – H2O
H = Hydrogen
O = Oxygen
Salt – NaCl
Na = Sodium
Cl = Chlorine
Percentage of Elements in the
Hydrosphere / Oceans
Element
%
Oxygen (O)
85.84
Hydrogen (H)
10.82
Chlorine (Cl)
1.94
Sodium (Na)
1.08
Magnesium (Mg) .13
This graph shows the composition of our…
Is Oxygen (O) the most important element in our atmosphere?
Only if you like breathing.
Is Oxygen (O) the most abundant element in our atmosphere?
NO!
N – (N) Nitrogen = 78%
O – (O) Oxygen = 21%
About 1 % of the atmosphere includes traces of other element and…
two important compounds.
CO2
H2O
Carbon Dioxide…plants need this.
Water Vapor (gas)…amount is variable.
The Earth’s Lithosphere /crust
is dominated by 5 compounds.
Compound
Silicon dioxide
Magnesium oxide
Ferrous oxide
Aluminum oxide
Calcium oxide
% mass
SiO2
43%
MgO
35%
FeO
9%
What do they all have in common?
Al2O3
7%
CaO
4%
Oxygen (O)
Compound
Silicon dioxide
Magnesium oxide
Ferrous oxide
Aluminum oxide
Calcium oxide
% mass
Crust Elements
% by mass
SiO2
42%
MgO
35%
Oxygen (O)
FeO
9%
Silicon (Si)
Al2O3
7%
Aluminum (Al)
CaO
4%
Iron (Fe)
Calcium (Ca)
These are the elements found in the
abiotic (non living) parts of
Earth’s Lithosphere / Crust.
47%
28%
8%
5%
4%
Common Elements for
Biotic Matter
Bio = life
In the
BIOSHPHERE
Life ?
Life =
•Grow
•Reproduce
•Respond
•Use Energy
C Carbon
H Hydrogen
N Nitrogen
O Oxygen
Four elements
are always
found in living
systems.
CO2
N
C6H12O6
sugar / carbohydrate
N
H2O
This is the chemistry of PHOTOSYNTHESIS !
“ORGANIC COMPOUNDS”
are bonded with the following elements
C Carbon
H Hydrogen
N Nitrogen
O Oxygen
P Phosphorus
S Sulfur
Remember
“CHNOPS”
(“sha nops”)