Transcript Teacher quality grant

Biology Partnership
(A Teacher Quality Grant)
Chemistry I
Subatomic particles
Electron configurations
Carbon molecules
Jill Hansen
Tammy Stundon
Gulf Coast State College
Panhandle Area Educational Consortium
5230 West Highway 98
753 West Boulevard
Panama City, Florida 32401
Chipley, Florida 32428
850-769-1551
877-873-7232
www.gulfcoast.edu
Welcome!
Pre-test
Q and A Board
Florida Next Generation
Sunshine State Standards
( SC.912.P.8.12):
• 1. Describe the properties of the carbon atom that make the
diversity of carbon compounds possible.
• NOTE: While this unit is relatively light on actual standards,
most of the material covered on the EOC requires a
comprehensive understanding of chemical basics.
• This lesson is designed for those who didn’t get it the first time!
DHMO
Why learn
chemistry?
Chemical basics are at
the root of every
biological function
• Neural impulse (Na/K
pump)
• Muscular contraction
(Ca ion uptake)
Percentage (%) of body’s composition
THE TOP 10 ELEMENTS FOUND IN YOUR BODY
THE “BIG 4”
96% of your body
is composed of
these 4 elements:
Oxygen (65%)
Carbon (18.5%)
Hydrogen (9.5%)
Nitrogen (3%)
OTHER (4%)
Calcium
Sulfur
Phosphorus
Sodium
Potassium
Chlorine
• Trace amounts (less than
0.1%) of 15 other elements are
also found in the body
Atomic Structure
• The universe is made up of matter
• Matter is made up of atoms
– Anything that takes up space
and has weight
Imagine dividing a gold
ring in half, forever
Atom =
• The smallest piece of gold possible is
uncuttable
called an atom. If you divided it into
smaller pieces, it would no longer be gold.
An atom is the smallest basic unit of matter.
An element is one type of atom.
Carbon
Gold
Each of the elements is
however made up of 3
fundamental particles
Copper
AN ELEMENT IS A SUBSTANCE THAT CANNOT BE BROKEN
DOWN CHEMICALLY INTO ANY OTHER SUBSTANCE
Atomic Structure
All atoms have 3 fundamental particles
– The nucleus has protons and neutrons.
– Electrons are in energy levels outside nucleus.
Oxygen atom (O)
Nucleus:
8 protons (+)
8 neutrons
outermost energy level:
6 electrons (-)
inner energy level:
2 electrons (-)
THE ATOM: BASIC STRUCTURE
Nucleus
Hydrogen atom
1 Proton
0 Neutrons
1 Electron
Carbon atom
6 Protons
6 Neutrons
6 Electrons
Nucleus:
Proton Neutron Electron
Forces of attraction
between positive and
negative charges hold
the fast-moving
electrons (negative)
close to the nucleus
(positive).
Atomic Structure
So how do you know if you have an atom of copper, gold or silver?
How many protons
an atom has
determines who it is
Cu = 39
Ag = 47
Au = 79
Atomic number is
the number of
protons
Cookium diagnostic
A KEY TO THE ELEMENTS
ATOMIC NUMBER
The number of protons found
in the atom’s nucleus
ELEMENT SYMBOL
Abbreviation of the element
ELEMENT NAME
ATOMIC MASS
Combined mass of the atom’s
protons and neutrons
Atomic Structure
So how do you know how many electrons and neutrons there are?
A neutral atom will have
equal numbers of protons
and electrons
+
P
=
E
The number of neutrons can
be determined by subtracting
the atomic number from the
atomic mass
P+N (atomic mass) –
P (atomic #) = N
Element
Atomic
Mass
Atomic
Number
Protons
Neutrons
Electrons
Ca
40
20
20
20
20
F
19
9
9
10
9
B
11
5
5
6
5
Atomic Basics Worksheet
Atomic Structure
Where are the electrons found?
Atoms are most stable if
they have a filled (or empty)
outer layer of electrons
Except for H and He, a
filled layer contains 8
electrons – an octet
Atoms will gain, lose, or share
electrons to make a full or
completely empty outer layer
ELECTRON SHELLS AND ATOM STABILITY
ELECTRON SHELLS
Electrons move around the nucleus in designated areas
called electron shells. An atom can have as many as seven
electron shells in total.
First electron shell
(capacity: 2 electrons)
Second electron shell
(capacity: 8 electrons)
Vacancy
The chemical characteristics of an atom
depend upon the number of electrons in its
outermost shell.
An atom’s electrons determine whether an atom will bond
with another atom as well as who it will bond with
Chemical Changes
When atoms exchange or share electrons, a new
product (a compound or molecule) is produced.
This is called a chemical change.
In a chemical change:
• reacting substances form new
substances with different
compositions and properties.
• a chemical reaction takes place.
Change
Chemical
Melting cheese
Milk souring
√
√
Ripping paper
Chemical Change Lab
Bike rusting
Physical
√
√
After the Lab: Balloon Buddy
Your challenge: get the balloon to kiss you
Simulation
Ions (charged atoms)
follow the rule that
opposites attract
Static electricity is a
reflection of the difference in
charges between objects
ELECTRON SHELLS AND ATOM STABILITY
ATOM STABILITY
Atoms become stable when their outermost shell is
filled to capacity. Stable atoms tend not to react or
combine with other atoms.
Unstable atoms
Stable atoms
Hydrogen atom
Helium atom
Nitrogen atom
Neon atom
Only when atoms have electron
vacancies in their outermost shell
are they likely to interact with
other atoms.
Ions form when atoms gain or lose electrons
• An ion is an atom that has gained or lost one or
more electrons.
– positive ions (cation)
– negative ions (anion)
• Ionic bonds form between oppositely charged ions.
gained electron
Na loses an
electron to CI
Sodium atom (Na) Chlorine atom (CI)
ionic bond
Sodium ion (Na+)
Chloride ion (CI-)
IONS ARE CHARGED ATOMS
An atom that loses one or more electrons becomes
positively charged, while an atom that acquires
electrons becomes negatively charged. This transfer
of electrons is driven by the fact that atoms with full
outer electron shells are more stable.
Donated electron
Na
Sodium ion
NET
CHARGE
Cl
11 Protons
10 Electrons
Chloride ion
17 Protons
18 Electrons
Positive
Negative
Ionic Bonds
Formed between ions
OPPOSITE CHARGES ATTRACT
COVALENT BONDS
1 Hydrogen atoms are
most stable when their
outer electron shell is
filled to capacity. They
can achieve this by
sharing electrons in a
covalent bond.
2 The nuclei come closer
together and the two
electrons begin to circle
around both of them. The
new H2 molecule is very
stable.
Hydrogen
atom
Hydrogen
atom
H2 molecule
Covalent bonds form electrically neutral molecules. Covalent
bond are very strong bonds, common in most organic molecules
Covalent Bonds
A molecule is made of atoms sharing electrons
– water (H2O)
– carbon dioxide (CO2)
Covalent Bonds
Molecule
A chemical structure held together by covalent bonds
The chemical structure shows the number of each element forming the
molecule (CH4)
2 IONIC BOND
An attraction between two
oppositely charged ions,
forming a compound.
3 HYDROGEN BOND
An attraction between the
slightly positively charged
hydrogen atom of one molecule
and the slightly negatively
charged atom of another.
Chemical Bonds Rap
Chemical Bond
SUMMARY: THREE TYPES OF BONDS
Strongest
H2 molecule
Bond Strength
1 COVALENT BOND
A strong bond formed when
atoms share electrons in order
to become more stable,
forming a molecule.
NaCl compound
Weakest
H2O
H2O
The Human Element Activity
• At your groups, decide who is
your ‘model’ and dress them
up in a trash bag.
• You will be assigned an
element, decide how many
valence electrons it has and
inflate and attach the correct
number of balloons
• Determine your ion, and
create a tag to wear
• Now BOND!
Periodic Trends
Periodic Table
In ascending atomic
number (mass usually
follows trend)
Valence electrons can be
determined by what
group the atom is in
Periods (horizontal)
Groups (vertical)
Trend doesn’t work well for the transition elements
The total number of
energy levels can be
determined by the period
Alien Periodic Table
• NASA’s instructions:
– Organize the aliens in a rectangular block.
– Each group (vertical column) must be the
same in some way and must have some
feature that changes regularly as you move
down the group.
– Each period (horizontal row) must also
share one thing in common and also must
have one feature that changes regularly as
you go across the periodic table.
by John Bergmann and Jeff Christopherson
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2
3
4
5
6
7
8
2
3
4
5
Answer Key
1
1
2
3
4
5
2
3
Why is this one wrong? 6
7
8
Chemical Reactions
The job of a chemical reaction is to
depict the kind of reactants and
products and the relative amounts in
a reaction.
C + O2 = CO2
Symbols represent elements,
formulas describe compounds, and
chemical equations describe a
chemical reaction
Reactants are what you use,
products are what you get
Chemical Symbols
The subscripts
tell you how
many atoms of a
particular
element are in a
compound. The
coefficient tells
you about the
number of
molecules of the
compound.
Balancing Reactions
Due to the Law of
Conservation of Mass:
matter cannot be
created nor destroyed.
An equation must be
balanced (it must have
the same number and
kinds of atoms both
before and after a
reaction.
Think of a recipe without any measurements
Reaction Rate Demo
When balancing a chemical reaction you may add
coefficients in front of the compounds to balance the
reaction, but you may not change the subscripts.
Changing the subscripts changes the compound.
Subscripts are determined by the valence electrons
(charges for ionic or sharing for covalent)
Isotopes
Going back to those neutrons…
Elements with the same number of protons but
different number of neutrons are called isotopes
Isotopes
Neutron
+ + +
Electrons
Nucleus
+
+
+
Nucleus
Carbon-12
Neutrons 6
Protons
6
Electrons 6
As istopes decay,
the release nuclear
particles at a rate
called a half life
Nucleus
Proton
Proton
+
+ +
+
Neutron
Electrons
+
+
Carbon-14
Neutrons 8
Protons
6
Electrons 6
Nucleus
Isotopes
Knowing an atoms
half life allows us to
determine the age of
organic items based on
their relative amounts
of isotopes
Decay of Candium
Follow up
• Q&A
• Post Test
• Give-a-ways
• Extenstions
– Symphony of Science
– Powers of Ten
– Khan Academy