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Composition of the Earth
Essential Questions
1.
2.
Examine the differences between changes and properties of matter.
How are subatomic particles arranged within an atom and is their a reason that
they are arranged in this manner?
3. What is matter and how does it behave?
4. How is the periodic table used to identify the characteristics and properties of
metals, nonmetals, and metalloids?
5. How are minerals identified?
6. Explain how minerals and rocks are a result of Earth’s regular pattern of change
and natural cycles?
7. How are environmental resoruces classified?
8. What effect does human activities have on natural resources?
9. What are the drawbacks and benefits of current energy sources?
10. How can we provide the energy we need while maintaining ecological balance?
Chemical and Physical Properties and Changes
Physical Property:
• can be observed without changing the substance
• Examples: color, hardness, density, size, shape
Physical Change:
• matter changes its physical properties
• no new substances are formed
• State changes are physical changes
• melting, boiling, freezing, evaporation,
condensation
Chemical Property:
• determines how a substance will react to
form new substances
Chemical Change:
• new substances are formed
• Examples: rusting, rotting, burning,
decaying
To determine chemical and physical
properties and changes, ask this:
• Are new substances being formed or could
they be formed?
YES – chemical
NO - physical
• Is something happening or could something
happen?
YES – change
NO - property
Identify the following as a physical
change, physical property, chemical
change, or chemical property.
1.
2.
3.
4.
5.
6.
Emeralds are green.
Calcite is reacting with acid.
Sugar is dissolving in water.
Clouds form when water condenses.
Water is boiling at 100°C.
Acid rain will break down limestone.
Atoms and Elements
• element:
• made up of one kind of atom
• each has a name and chemical symbol on
periodic table
• atom: smallest part of element that has properties
element
• nucleus: central core of the atom
• Atoms are made of three basic parts:
• proton: positively charged, inside nucleus
• neutron: no electric charge, inside nucleus
• electron: negatively charged, outside
nucleus
# of protons and electrons are equal
• compound: atoms of different elements
chemically combined
• mixture: two or more substances
physically combined
• can be separated by physical change
• chemical formula: combination of
chemical symbols to represent a compound
• show # and type of elements
Bohr Models
• Created by Neil's Bohr.
• Shows the as a small positively charged
nucleus surrounded by negatively electrons.
Bohr Models
• Atomic number = number of protons and electrons
• Rounded Mass Number – Atomic Number= Neutrons
• Neutrons + Protons = Mass number
Location of Subatomic Particles
• Protons: inside Nucleus
• Neutrons: inside Nucleus
• Electrons: outside in orbitals
Number of Electrons that can be
held in each energy level.
• Use the formula 2n2 to determine the
number electrons to be held in each orbital.
• N = the level one is trying to determine.
• EXAMPLE
• How many electrons can be held on the 3rd
level?
• 2(3)2= 18 electrons
Example of (Al) Bohr Model
• Aluminum
• Protons: 11 (atomic number)
• Electrons: 11 (atomic number)
• Neutrons: 12 (rounded mass # - atomic number)
Practice
• Create Bohr models for the following in Groups!
•
•
•
•
•
Carbon (C)
Neon (Ne)
Silicon (Si)
Copper (Cu)
Sodium (Na)
Homework
• Create Bohr models for the following:
• Iron (Fe)
• Silver (Ag)
• Mercury (Hg)
Matter
= the study of matter
► Matter = anything that has mass and takes
up space (has volume)
► CHEMISTRY
Classification of Matter
Elements
►
There are currently 118 known elements
►
The elements are named by:
- the scientist (Es-einsteinium)
- the university (Bk-berkelium)
- the town (Cf-californium)
- its latin name (Au-aurum)
http://en.wikipedia.org/wiki/List_of_chemical_element_name_etymologies
Elements
►
Each element has its own unique physical
and chemical properties
Element
Physical
Property
Chemical
Property
Sodium-Na
Solid, shiny,
malleable
Very reactive,
loses e-
Chlorine-Cl
Gas, green
Very reactive,
gains e-
Isotopes
► Atoms
of the same element that have a
different number of neutrons because their
mass is different from the original element.
► Examples
 Carbon generally has a mass of 12, which means it
will have 6 neutrons.
 Carbon-14 has a mass of 14, which means it will
have 8 neutrons.
Isotopes
Periodic Table
A chart of the elements
► Group/Family:
- vertical column (18)
- elements are listed with others
having similar properties
► Period
- horizontal rows (7)
- elements having the same number
of energy levels
►
Metals
► Physical
Properties:
- malleable: bendable
- ductile: stretches into thin wire
- conducts heat & electricity easily
- has luster
► Chemical Properties:
- tend to lose e-’s
- the more to the left on the periodic table,
the more reactive/metallic
Nonmetals
► Physical
Properties:
- brittle: breaks when bent
- nonconductor of heat & electricity
- dull
► Chemical Properties:
- tend to gain e-’s
- the more to the right on the periodic
table, the more reactive/nonmetallic
Metalloids
► Will
tend to gain or lose electrons,
depending on the element it bonds with
► Mixed properties
Noble Gases
Noble Gases
► Nonreactive
due to the full
outer energy level
(*8 e-’s)
► Octet rule = ALL
atoms “want”
eight outer e-’s
Halogens
► MOST
reactive
nonmetals
► Gaining 1 e- would
give octet
Alkali Metals
► Most
reactive
metals
► Losing 1 e- would
give octet
Valence e- = outermost e-
Compounds
Compounds
► Compound
= two
or more different
elements chemically
bonded
► Molecule = two or
more atoms bonded
together
Compounds
► Why
aren’t these compounds?
► Why are they molecules?
Types of Compounds
► Ionic
(ionic bond)
- metal - nonmetal
- formed by electron transfer
► Molecular (covalent bond)
- nonmetal - nonmetal
- formed by sharing of electrons
Formulas
► Provide
the:
- type of elements
- number of atoms of each element
► Examples: (count the atoms)
C8H10N4O2
subscript
Al(NO3)3
Types of Bonding
1. Ionic Bonds
2. Covalent Bonds
Types of Bonding
Ionic
- metal - nonmetal
- formed by electron transfer
► Covalent
- nonmetal - nonmetal
- formed by sharing of electrons
►
Ion Formation
(electron transfer)
1. cation formation:
- metal atom loses valence electrons
- metal ion with positive charge forms
► 2. anion formation:
- nonmetal atom gains valence electrons
- nonmetal ion with negative charge forms
►
http://gpc.edu/~pgore/PhysicalScience/ionic_bond_animation.gif
Ionic Bonding
Simple Ionic Nomenclature
► Metal
name goes first – no change
► Nonmetal name goes second – change ending
to –ide.
► Number of atoms in formula doesn’t matter
 (WE DO NOT CARE ABOUT SUBSCRIPTS AT THIS
POINT)!
Ex: MgCl2
Li2O
magnesium chloride
lithium oxide
Ionic Nomenclature (binary) Practice
The number of atoms do NOT affect the name
► Ex: MgCl2
magnesium chloride
►
1. MgO
4. BeCl2
2. Li2O
5. K2S
3. AlF3
6. NaF
Ionic Nomenclature
(nonbinary)
If there are more than 2 elements, a polyatomic
ion must be present
► Simply write the names of the metal and the ion
► Ex: MgSO4
magnesium sulfate
►
Na2CO3
Al(NO3)3
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Polyatomic-FormulatoName.html
Ionic Nomenclature (binary)
compounds have 2 elements
► 1st element name (metal) is unchanged
► 2nd element name (nonmetal) ends –ide
► Binary
► Ex:
NaCl
sodium chloride
http://misterguch.brinkster.net/practiceworksheets.html
Ionic Bonding
Writing Ionic Formulas
►
RULES
1. the metal is always written first
2. total positive charges must equal total
negative charges
3. use subscripts to state how many ions must
be present in the formula
4. never include charges in the formula
Ex: magnesium chloride
Writing Binary Ionic Formulas
1.
2.
3.
4.
5.
6.
7.
Calcium oxide
Calcium chloride
Lithium sulfide
Lithium bromide
Aluminum phosphide
Aluminum iodide
Aluminum oxide
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Binary-Fixed-NametoFormula.html
Writing Nonbinary Ionic Formulas
Match the metal charge to
the charge of the poly ion
by using subscripts
► Use parentheses on poly
ion ONLY if multiplying by
a subscript
► Ammonium (NH4+) is the
ONLY positively charged
polyatomic ion
►
1.
2.
3.
4.
5.
6.
7.
8.
calcium carbonate
lithium phosphate
barium nitrate
potassium chlorate
ammonium chloride
ammonium sulfate
zinc chromate
silver nitrate
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Polyatomic-NametoFormula.html
The Stock System
►
Transition elements
may have more than
one type of charge
Metal
Possible
Charges
Fe
+2, +3
Cu
+1, +2
Sn
+2, +4
The Stock System
►
1.
The charge can be determined from the:
Name: a Roman numeral is used to give the
charge
Ex: copper (II) oxide
Cu+2 + O-2  CuO
Practice:
tin (IV) chloride
iron (II) sulfide
The Stock System
►
2.
The charge can be determined from the:
Formula: work from the known charge on the anion
and the rule that positive and negative charges must be
equal
Ex: Fe2O3
Oxygen has a known charge of -2
3 oxygens have a charge of -6
 the 2 irons have a charge of +6
and each iron has a charge of +3
iron (III) oxide
http://misterguch.brinkster.net/practiceworksheets.html
The Stock System
►
1.
2.
3.
4.
5.
Write the formula
Iron (II) oxide
Gold (III) chloride
Tin (IV) bromide
Mercury (II) chloride
Manganese (II)
chlorate
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Binary-Comm-NametoFormula.html
The Stock System
►
1.
2.
3.
4.
5.
Write the name:
CuBr
Fe2O3
Sn3P4
PbBr4
Hg2F2
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Binary-Stock-FormulatoName.html
Covalent Nomenclature
►
Compounds having
covalent bonds form
molecules
Molecular nomenclature
uses prefixes to state
how many atoms of
each element are found
in the compound
► Never use mono- with
the 1st element
►
1
mono
2
di
3
tri
4
tetra
5
penta
6
hexa
7
hepta
8
octa
9
nona
10
deca
Covalent Compounds
► NO
METALS
ALLOWED!
Simple Molecular Nomenclature
Ex: P2O5
► Use prefix with first element
diphosphorus
► Use prefix with second element AND end
with –ide
pentaoxide
► Do NOT use the mono prefix on the 1st
element
http://www.pafaculty.net/biology/keith/KR_Graph_site/molec_nomenclature_page.htm
Binary Molecular Nomenclature
►
►
1.
2.
3.
4.
5.
Ex: P2O5 is diphosphorus pentaoxide
Name the following molecular compounds
S2Cl2
UF6
ClO2
BF3
N 2 S5
http://dbhs.wvusd.k12.ca.us/webdocs/Nomenclature/Binary-Greek-FormulatoName.html
Binary Molecular Nomenclature
►
Write the formulas for the following
molecular compounds:
1.
Bromine trioxide
Tetraarsenic decaoxide
Dinitrogen trioxide
Boron mononitride
Xenon tetrafluoride
2.
3.
4.
5.
Chemical Reactions
Signs of Chemical Change
► 1.
color change
► 2. formation of a gas
► 3. formation of a precipitate
► 4. change in energy (temp. change)
-
These are the most common
A change in energy ALWAYS occurs
A NEW substance with NEW properties is
always formed
Change in Energy
► Endothermic:
energy is
feels cold
► Exothermic:
energy is
feels warm
Law of Conservation of Mass
► What
goes in….must come out!
Balancing Equations
► Reactants
= substances combined that go
into the reaction
► Products = new substances formed that
come out of the reaction
Reactants  Products
Chemical Equations
A+B  C+D
REACTANTS
PRODUCTS
Balancing Equations
► law
of conservation of mass: mass of the
reactants must equal mass of the products
mass Reactants  mass Products
► We
now know that (#atoms)(atomic mass) = mass
► This means that:
#atoms Reactants  #atoms Products
Rules - Balancing Equations
1.
2.
1.
Count the atoms of one element on both
sides of the equation
N2 + H2  NH3
Use coefficients (multiples) to increase
atoms of an element
N2 + 3H2  2NH3
NEVER change a formula (change/insert a
subscript)
N2 + H3  N2H3
Balancing Equations - practice
1.
H2 +
O2 ---->
H2O
2.
Mg +
P4 --->
Mg3P2
3.
Cu +
O2 ---->
Cu2O
Balancing Equations - tips
► Look
for polyatomic ions
► Count the ion as a unit
CaCl2 + AgNO3 ----> AgCl + Ca(NO3)2
Balancing Equations - tips
► Check
for elements that occur more than
once on one side of an equation – sum the
atoms.
(NH4)2CO3 ---> NH3 + CO2 + H2O
What is a Mineral?
Must meet 5 criteria to be classified as a mineral
1. Occur naturally – can be found on Earth, not
manmade
2. Inorganic - not formed from living things or their
remains
3. Solid – have definite volume and shape
4. Definite chemical composition – element or
compound
5. Crystal structure - atoms arranged in definite
pattern that repeats itself, flat sides, sharp edges and
corners
• Minerals are very difficult to identify just
by looking at them.
Physical properties help
identify minerals.
1. color – only a few minerals have a
characteristic color
2. luster – describes the way a mineral
reflects light
•
•
metallic – reflects light the way polished
metal does
nonmetallic – does not reflect much light
3. hardness – ability of a mineral to resist
being scratched
•
•
most useful for mineral identification
Moh’s Hardness Scale
• p. 52 in your book
• compares hardness of minerals to ten
“standards”
• numbered 1-10
• 1 is softest, 10 is hardest
Moh’s Hardness Scale
4. streak – color of the powder left behind
when a mineral is rubbed against a hard,
rough surface
5. density – amount of matter in a given
space; how closely packed the mineral is
6. crystal shape – six characteristic shapes
7. cleavage and fracture – describes the
way a mineral breaks
•
•
cleavage – split along smooth, definite
surfaces
fracture – breaks along rough, jagged edges
Cleavage
Fracture
8. special properties – properties
characteristic of only 1 mineral
•
•
•
magnetic
acid test
taste
Moh’s Hardness Scale Virtual Lab
• http://academic.brooklyn.cuny.edu/geology/
leveson/core/linksa/hardex_2a.html
What are Rocks?
• Rock: hard substance composed of one or
more minerals
• Geologists: scientists who study rocks
3 Classifications for Rock
I.
Sedimentary Rocks
•
form from sediments that pile up and
become pressed together over time
Sedimentary Rock
3 Main Types of Sedimentary Rock
1. Clastic Rocks
•
made of pieces of other rocks
2. Organic
• formed form material that once was living
3. Chemical
• formed when a body of water dries up,
leaving behind the minerals dissolved in
the water
II. Igneous Rocks
•
•
•
form when hot, liquid magma cools within
the earth
Classified by composition and texture
2 Kinds
1. extrusive rocks: formed from lava (at
or near surface)
2. intrusive rocks: formed from magma
(deep in the earth)
Igneous Rock
III. Metamorphic Rocks
•
form when heat, pressure, or chemical
reactions change existing rocks into new
rocks
2 Main Types
classified by texture (arrangement of grains)
•
•
1.
2.
Foliated – mineral crystals are arranged in
layers
Unfoliated – do not have bands
Metamorphic Rock
• Rock Cycle: continuous changing of rocks
over a long period of time
Rock Cycle Processes
•
•
•
•
•
Sedimentary: Cementation and Compaction
Sediments: Weathering
Metamorphic: Heat and Pressure
Igneous: Cooling and Crystallization
Magma: Melting
The Rock Cycle
Resources and Energy
Types of Resources
• Renewable Resources- Can be replaced within a
human life-time or as they are used.
• Examples: Air, water, plants
• Nonrenewable Resources: A natural resource
that cannot be re-made or re-grown at a scale
comparable to its consumption.
• Examples: Fossil Fuels (Oil, Coal, Petroleum)
Ores
• Deposits or minerals from which metals and
nonmetals can be removed profitably.
• Examples: Fe (iron) can be extracted from
magnetite and hematite.
Fossil Fuels
• Coal, Petroleum, Natural Gas
• Consists of hydrocarbons.
• Hydrocarbons contain multiple hydrogen
bonds.
Coal
• Dark-colored, organic rock.
• Formed from the process or carbonization.
• Carbonization: occurs when partially
decomposed trees and other plants are buried in
swamp mud.
• Mined for consumption!
HOW IS COAL MADE ???
Oil and Natural Gas
• Found under ground between folds of rock
and in areas of rock that are porous and
contain the oils within the rock itself.
• Drilled for consumption!
HOW ARE OIL AND GAS MADE
???
Fossil Fuels and the Environment
• Strip mining of coal leaves deep ditches
where coal is removed, which allows
erosion to act upon it.
• Air Pollution is caused by burning of coal
with a high sulfur content, which results in
acid rain production.
• Oil Spills occur due to drilling.
Alternative Energy
• Alternative energy resources other than
fossil fuels.
• Examples: Nuclear Fusion and Fission,
Solar Energy, Geothermal Energy, Wind
Energy, Hydroelectric Energy, and Biomass
Nuclear Energy: Nonrenewable
• Nuclear fission uses uranium to create
energy.
• Nuclear Fusion is used with many isotopes
to create energy.
• Two Types
• Fission: Splitting Atomic Nuclei
• Fusion: Combining Atomic Nuclei
Nuclear Fission: Nonrenewable
• Splitting of the nucleus of a large atom into
two or more smaller nuclei to release a large
amount of heat energy.
Nuclear Fusion: Nonrenewable
• Combining of smaller nuclei to form larger
nuclei to release energy.
• Solar Radiation is created in this way.
Alternative (Renewable) Energy
SOLAR
• Energy from the sun
Solar Power
• Benefits
• Abundant
• No greenhouse gases,
few other pollutants
• Simple, minimal
repair needed
• Cheap over the long
term
• Negative
• Has limitations, night,
some locations better such
as south rather than north
facing slopes
• Initial capital outlay can
be high. (COST)
GEOTHERMAL
Energy from
Earth’s heat.
Geothermal
Cons
• Can be used for electricity
generation, space heating,
cooking & low temperature
industrial
• Inexpensive after initial
outlay
• No greenhouse gas emission
Pros
• Same problems as we see
with oil drilling
• Localized distribution- only
assessable to certain areas
WIND
Energy from the
wind.
Effects of windpower
Pros
Cons
•
•
•
•
• Some noise pollution
• Metal blades interfere with
TV & radio reception
• No evidence for bird death,
but can kill bats
No greenhouse gases
Cheap
Abundant
Simple
BIOMASS
Energy from
burning organic or
living matter.
Biomass
PROS
CONS
• Burning biomass gets rid of
solid wastes
• Creates Energy
• Creates new markets for
crops, which in turn creates
revenue for farmers.
• Releases CO2 and other
gases associated with
combustion
• Creates solid waste from ash
WATER or HYDROELECTRIC
Energy from the
flow of water.
Hydroelectric Power
PROS
CONS
• Can generate electricity
• Can do mechanical work,
e.g. grind grain
• No greenhouse gases
• Initial construction provides
jobs
• Flooding the land
• Displacement of local
inhabitants
• Tectonic activities
(Earthquakes)
• Loss of species (aquatic &
terrestrial)
• Loss of normal nutrient flow
down river