Bell Ringer
1) Which nucleus below belongs
to the element on the right?
(red = proton, yellow = neutron)
a)
b)
c)
d)
2) Your friend stands on a scale and
proclaims that his mass is 170 pounds.
You answer:
a) That is not your mass. Your mass is
how much space you take up. 170
pounds is your weight
b) Your mass is equal to the pressure of
gravity pulling on you. That is why your
mass is 170 pounds.
3) There are four elements associated with
life – they make up 90% of all living things.
Which answer lists them?
a) Carbon, Nitrogen, Phosphorus,
Magnesium
b) Carbon, Oxygen, Hydrogen, Silicon
c) Nitrogen, Beryllium, Hydrogen, Oxygen
d) Hydrogen, Oxygen, Nitrogen, Carbon
4) The pictures below best represent:
a) neutrons
b) isotopes
c) protons
d) atoms
Chemical
Compounds
Still Chemistry...
• Most elements do not exist solely as that
element.
• Atoms of most elements will readily combine
with other atoms to form compounds.
Still Chemistry...
• Chemical compounds are found all around us.
• Do you recognize these common chemical
compounds?
- NaCl =
- C12H22O12 =
- CH2CH3OH =
- NaOCl =
Still Chemistry...
• Chemical compounds are found all around us.
• Do you recognize these common chemical
compounds?
- NaCl = Table Salt
- C12H22O12 =
- CH2CH3OH =
- NaOCl =
Still Chemistry...
• Chemical compounds are found all around us.
• Do you recognize these common chemical
compounds?
- NaCl = Table Salt
- C12H22O12 = Sucrose (Sugar)
- CH2CH3OH =
- NaOCl =
Still Chemistry...
• Chemical compounds are found all around us.
• Do you recognize these common chemical
compounds?
- NaCl = Table Salt
- C12H22O12 = Sucrose (Sugar)
- CH2CH3OH = Mouthwash
- NaOCl =
Still Chemistry...
• Chemical compounds are found all around us.
• Do you recognize these common chemical
compounds?
- NaCl = Table Salt
- C12H22O12 = Sucrose (Sugar)
- CH2CH3OH = Mouthwash
- NaOCl = Bleach
Still Chemistry...
• The chemical and physical properties of
elements change when they become
compounds.
• Sodium (Na) is a solid that reacts
explosively with water.
Still Chemistry...
• The chemical and physical properties of
elements change when they become
compounds.
• Sodium (Na) reacts explosively with water.
• Chlorine (Cl) is a poisonous gas
Still Chemistry...
• The chemical and physical properties of
elements change when they become
compounds.
• Sodium (Na) reacts explosively with water.
• Chlorine (Cl) is a poisonous gas
• But, together, they make table salt (NaCl)
+
=
Still Chemistry...
• Most atoms are not stable in their natural
state, so they react with other atoms
(forming compounds) to become more
stable.
Still Chemistry...
• Most atoms are not stable in their natural
state, so they react with other atoms
(forming compounds) to become more
stable.
• Chemical compounds are formed by
atoms joining together.
• These atoms are held together by
chemical bonds.
Still Chemistry...
• Most atoms are not stable in their natural
state, so they react with other atoms
(forming compounds) to become more
stable.
• Chemical compounds are formed by
atoms joining together.
• These atoms are held together by
chemical bonds.
• Bonding is all about the
electrons!
Chemical Bonds...
• There are two types of chemical bonds:
Chemical Bonds...
• There are two types of chemical bonds:
Covalent Bonds
Ionic Bonds
Covalent Bonds
• Covalent bonds – a bond that forms
between two atoms that share one or
more electrons.
Covalent Bonds
• Covalent bonds – a bond that forms
between two atoms that share one or
more electrons.
• Water is made up of one oxygen atom and
two hydrogen atoms held together by
covalent bonds.
Covalent Bonds
• An atom is stable when it has 8 electrons
in its outermost shell
• The only exception is hydrogen, which is
stable with 2 electrons.
Covalent Bonds
• Based upon this Rule of 8, an oxygen
atom with six electrons will gladly bind to
two hydrogen atoms to obtain a total of
eight electrons.
Ionic Bonds
• Ionic bonds – a bond that forms
between two charged atoms in
which electrons are transferred
from one atom to the other.
Ionic Bonds
• Ionic bonds – a bond that forms between two
charged atoms in which electrons are
transferred from one atom to the other.
• Sodium (Na) has one electron in its outer shell.
• Chlorine (Cl) has seven electrons in its outer shell.
Ionic Bonds
• Because both atoms want to have 8 electrons
in their outer shell, sodium gives away its 1
electron.
Ionic Bonds
• Because both atoms want to have 8 electrons
in their outer shell, sodium gives away its 1
electron.
• Both atoms now have 8 electrons in their outer
shells.
Ionic Bonds
• This sharing of electrons, though, causes the atoms
to become charged.
• Because sodium lost an electron, it gains a positive
charge.
• Chlorine, which gained an electron, is now negatively
charged.
• A charged atom is called an ion.
Ionic Bonds
• The positive charge of the sodium and the
negative charge of the chlorine attract each
other, creating the ionic bond.
Ionic Bonds
• The positive charge of the sodium and the
negative charge of the chlorine attract each
other, creating the ionic bond.
• “Opposites attract!”
• Example: balloon and hair
Determining the Number of Electrons
1 2
1
2
3
4
5
6
7
8
3 4 5 6 7
Red numbers = # of electrons
Blue numbers = # of orbitals (circles)
A “Bonding” Experience
• Everyone will be assigned an element.
• Remember (unless you are hydrogen),
that you need a total of 8 electrons in your
outer shell to be stable.
• Your job is to find another student (or
more) in the room to bond with so that you
both are stable.
• You will have thirty seconds to do so. Any
student not “bonded” will be out.
Creating Chemical Compounds
Make some Hydrochloric Acid
(HCl)
Creating Chemical Compounds
Make some Hydrochloric Acid
(HCl)
1) First, identify which two elements are part
of this compound.
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
1) First, identify which two elements are part
of this compound.
Hydrogen – H
Chlorine - Cl
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
2) Draw Hydrogen
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
2) Draw Hydrogen
1 2
1
2
3
4
5
6
7
8
3 4 5 6 7
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
2) Draw Hydrogen
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
3) Draw Chlorine
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
3) Draw Chlorine
1 2
1
2
3
4
5
6
7
8
3 4 5 6 7
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
3) Draw Chlorine
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
4) Put them together by sharing an electron
Creating Chemical Compounds
Make some Hydrochloric Acid (HCl)
4) Put them together by sharing an electron
Chemistry Practice
1) Make Water (H2O)
Chemistry Practice
1) Make Water (H2O)
1 2
1
2
3
4
5
6
7
8
3 4 5 6 7
Chemistry Practice
1) Make Water (H2O)
Exit Slip
1) The two types of chemical bonds are:
a) electrons and protons
b) ionic and covalent
c) ionic and bivalent
d) van der Waals and Hydrogen
2) Silicon dioxide (SiO2) is formed by the
sharing of electrons between the two
elements. This is an example of:
a) an ionic bond
b) a covalent bond
c) an atom
d) a hybrid molecule
Exit Slip
3) Nitrogen has 5 electrons in its outer shell.
With which atom(s) should it bond to
become stable?
a) a Boron atom – 4 electrons
b) a Carbon atom – 5 electrons
c) 2 Lithium atoms – 2 electrons apiece
d) 3 Hydrogen atoms – 1 electron apiece
4) An ion is a _____. It is involved in_____
a) charged atom ; covalent bonding
b) charged atom ; ionic bonding
c) a neutral atom ; covalent bonding
d) a neutral atom ; ionic bonding
Energy
Energy
• Energy – the ability to do work.
Energy
• Energy – the ability to do work.
• Energy occurs in various forms and can be
converted from one form to another.
• Example: Light Bulb
– Electrical energy is converted
to radiant energy (light) and
thermal energy (heat)
Energy
• Types of energy include:
– Solar
– Chemical
– Mechanical
– Thermal
– Geothermal
– Hydroelectric
Energy
• Types of energy include:
– Solar
– Chemical
– Mechanical
– Thermal
– Geothermal
– Hydroelectric
Try to think of an example for each one
Energy
• Types of energy include:
– Solar – the sun
– Chemical – gasoline
– Mechanical – screwdriver
– Thermal – fire, match
– Geothermal – geyser
– Hydroelectric – dam
Chemical Energy
• Living things use chemical processes
(during metabolism) to derive energy for
their life processes.
• After you eat, your body begins to break
down the food using chemicals in your
digestive system, resulting in energy
gained.
Chemical Energy
• Two examples of chemical energy:
– Film Canister Gun
• The fumes of ethanol are highly flammable. By
trapping them inside the canister and adding a
spark, the vapors ignite.
• The chemical energy in the ethanol is transformed
into thermal, kinetic and sound energy.
– Coke Fountain
• Chemicals in the diet Coke (caffeine, potassium
benzoate and aspartame) and the Mentos react
violently. Chemical energy is transformed into
kinetic energy and the Coke becomes a geyser.
• They concluded that the caffeine,
potassium benzoate, aspartame, and CO2
gas contained in the Diet Coke and the
gelatin and gum arabic ingredients of the
Mentos all contribute to the jet effect.[8] In
addition, the MythBusters theorized that
the physical structure of the Mentos is the
most significant cause of the eruption.