1. Molecule Notes pg 64tial Questions:
What are the basic differences of elements, molecules, and compounds?
What determines the number of molecules in a chemical equation?

2. From really small to really big….
You could start really small Subatomic particles of matter   - Atoms     - Molecules       - Macromolecules         - Cell organelles           - Cells             - Tissues               - Organs                 - Systems                   - Organisms                     - Populations                       - Ecosystems                         - Biomes                           - Planets                             - Systems with Stars                               - Galaxies                                 - The Universe                                   ...And finish really big. 
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3. Atoms
Lets Review –
Atoms are the basic building blocks of matter. Objects that take up space and have mass are called matter. Everything around you is made up of matter.
Atoms are made from subatomic particles called 
protons (+)(which carry a positive electrical charge)
neutrons (which carry no electrical charge)
electrons (-) (which carry a negative electrical charge).
The protons and neutrons cluster together in the central part of the atom, called the nucleus, and the electrons are found at different energy levels in an electron cloud.
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4. Elements
Lets Review –
A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons.
An element is a substance that is made entirely from one type of atom.
For example, the element hydrogen is made from atoms containing just one proton and one electron.
If you had very, very good eyes and could look at the atoms in a sample of hydrogen, you would notice that most of the atoms have no neutrons, some of them have one neutron and a few of them have two neutrons. These different versions of hydrogen are called isotopes.
All isotopes of a particular element have the same number of protons, but can have different numbers of neutrons.
If you change the number of protons an atom has, you change the type of element it is. If you change the number of neutrons an atom has, you make an isotope of that element.
All known elements are arranged on a chart called the Periodic Table of Elements.
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5. Mixture
A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad, salt water and a mixed bag of M&M's candy.
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6. Molecules Molecules Examples of molecules O2 – oxygen
Molecules are a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound
Made up of two or more atoms
The atoms can be the same or different.
Examples of molecules
O2 – oxygen
O3 - ozone molecule
H2O – water
CO2 - carbon dioxide
H2SO4 – sulfuric acid
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7. Molecules
Oxygen atoms
Needs 2 electrons to
have a full outer shell
6 valence electrons in
an oxygen atom
Molecules
Formed when two or more atoms bond together chemically
Elements can bond with the same atoms or different atoms.
These bonds form as a result of the sharing or exchange of valence electrons among atoms.
Valence electrons are the electrons on the outermost energy level.
Oxygen molecule O2
Valence electrons are
always looking to fill the
outer most electron layer.
By sharing electrons both
oxygen atoms now have
complete outer shells.
Two oxygen atoms bonding by sharing electrons
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8. NaCl Compound Compounds Elements
A compound is a chemical substance formed when two or more different elements bond in a specific proportion.
The elements lose their individual chemical properties and the compound has new properties.
Poisonous gas
Explosive solid
NaCl
Compound
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9. Compounds
Compound
Chemical bonds are a result of the sharing or exchanging electrons among the atoms.
There are two types of bonding:
ionic bonding, where an electron from one atom is transferred to another atom. You wind up creating two ions as one atom loses an electron and one gains one.
covalent bonding, where electrons are actually shared between two or more atoms in a cloud.
The smallest unbreakable unit of a compound is called a molecule.
2 Hydrogen atoms
1 Oxygen atom
Water Molecule
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10. H2O H +H + O Chemical Formula Chemical Formulas
The recipe for a chemical substance
Tells the number of atoms of each element in a compound or molecule
Uses symbols for the elements present and subscripts (small numbers) to indicate the number of elements
Ex. H2O - water
H2O
H +H + O
subscript H H O
2 Hydrogen atoms and 1 oxygen atom
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11. 2H2 + O2 → 2H2O Chemical Equation Chemical Equations
A shorthand that scientists use to describe a chemical reaction
The number in front of the element symbol (called a coefficient) indicates the number of molecules.
If no coefficient appears in front of a molecule, we interpret this as meaning one.
Coefficient
2H2 + O2 → 2H2O
2 hydrogen molecules +
1 oxygen molecules =
2 water molecules
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12. Quick INB Action – Molecules Practice folder pg 65
Element
Molecules
Compounds
1. Quickly sketch the 3 circles
2. Draw each object in the correct
circle.
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13. Quick Action – Molecules Practice
Grab a partner and let’s practice. Is it a molecule or a compound?
Formula
Molecule
Compound
Element
Both
Compound and Molecule O2
NaCl
CH4 H2 H
Atoms elements and compounds
This would be a good short video to show at this time.
Write a rule that you can follow for determining the difference in a compound and a molecule?
Here is a hint… All ___________ can be ___________, but…..
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14. Quick Action – Molecules Practice
Grab a partner and let’s practice. Count the molecules in each balanced equation.
1. CH4 + 2O CO2 + 2H _____ CH4 _______ O2 _______ CO2 _________H20
2. 2Fe +3Cl FeCl _____ Fe _____ Cl2 _____ FeCl3
3. P4O10 + H2O H3PO _____ P4O10 ______ H2O _____ H3PO4
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15. Check for Understanding
Can You-
Describe the differences in an element, a molecule, and a compound?
Determine the number of molecules in a balanced equation?
Clear up any confusion and answer questions.
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16. Assessment folder pg 66
What are the basic building blocks for all matter?
What do we call a substance consisting of a single type of atom?
What is the difference between a molecule and a compound?
What are valence electrons?
When compounds are formed what happens to the properties?
What is the smallest unbreakable unit of a compound?
What is like a recipe for a chemical substance?
What is the part of the formula that tells the number of atoms of each element?
In a chemical equation, the number of molecules participating in the reaction?
In the chemical equation: 2H2 + 2O = 2H2O
How many Hydrogen atoms are there?
How many Hydrogen molecules are there?
How many oxygen atoms are there?
How many water molecules are there?
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