Download Standard 1:Atomic Structure + Elements, Compounds, Mixtures

Chemistry
Standard 1:Atomic Structure +
Elements, Compounds, Mixtures
Matter
Chemistry is the study of matter.
A chemist is a scientist that examines how substances interact
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Biochemist
Chemical Engineer
Pharmacology
Material Science
Atomic Structure
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Be able to describe how atoms make up
the matter of the universe.
What are the 2 regions of an atom and
what are their important properties?
Matter
Matter is anything that has mass and takes up space.
All matter in the universe is made up of different combinations of the 3 main
subatomic particles
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Protons
Neutrons
Electrons
These particles combine to form atoms.
Atoms
An atom is the smallest unit of matter that can be identified as an element.
Ex: Carbon atom, nitrogen atom, oxygen atom, gold atom
What do you have when you cut a bar of gold in half?
What if you cut it again?
And again?
Eventually you would get to the point where you have one single atom of gold.
An atom cannot be cut apart. Atomos means indivisible. If you broke an atom
apart it would reduced to its protons, electrons, and neutrons.
Atoms
If you were able to look closely
enough you would see that matter
is made up of an insane number
of atoms.
Atoms
This is the first actual picture of a hydrogen atom
Atomic Structure
An atom has 2 areas
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Nucleus
Electron Cloud
Nucleus
The nucleus of an atom is INCREDIBLY small. A hydrogen atom is 145000 times
bigger than its nucleus.
The nucleus
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is made of protons and neutrons.
is surrounded by the electron cloud.
contains nearly all of the mass of the atom
takes up almost no space
is positively charged
Electron Cloud
The electron cloud is made of electrons. The electrons move through the cloud at
incredible speeds.
The electron cloud
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is made of electrons
takes up almost all the space
has nearly no mass
Totally Unfair Pretend Pop Quiz hahahaha
Get out a halfsheet of notebook paper and close your notebooks
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Draw and label a diagram that has an electron cloud and a nucleus
What 2 particles are found in the nucleus
What particle is in the electron cloud?
Which region has all the mass and takes up almost no space?
Which region takes up all the space but has no mass?
What is all matter in the universe made up of?
Atoms are made of 99.999999999999% what?
First person to say dogs are better than cats gets candy
How small is an atom?
Start video 1 at 37 seconds
Protons, Electrons,
Neutrons
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Know the location, charge, and mass of each
subatomic particle
What determines the type of element?
How do you use an element box to determine
the number of PEN
Subatomic Particles
You will need to know the following table and diagram
Charge
Mass
Location
Proton
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1
Nucleus
Electron
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0
Electron
Cloud
Neutron
None
1
Nucleus
Atoms and Elements
Elements are the different types of atoms.
The type of element is determined by the number of protons.
Hydrogen
Helium
Lithium
1 Proton
2 Protons
3 Protons
Element Key
Element keys provide information about the element
Number of Protons
The atomic number is the number of protons
Nitrogen has 7 protons
Candy Question:
If you added a proton to a nitrogen nucleus, what would it be?
Number of Electrons
A stable atom has the same number of protons and electrons.
If an atom has 7 protons, it will also have 7 electrons.
Protons have a positive charge. Electrons have a negative charge. Opposite
charges attract. So protons will attract electrons until the atom is stable.
#of Electrons=# of Protons=Atomic Number
Candy Question:
How many electrons does gold have? Atomic symbol Au
Number of Neutrons
The atomic mass is the weight of all of the particles in an atom.
Since protons weigh 1, neutrons weigh 1, and electrons weigh 0. The atomic mass
is the number of protons + the number of electrons.
To find the number of Neutrons it is the Atomic Mass - Atomic number.
Bottom #-Top #
Always round the atomic mass
Candy Question:
How many neutrons are in an atom of lithium? Li
Why is the atomic mass a decimal?-Isotopes
The atomic mass is an average the estimated world supply of that atom.
Some atoms have the same number of protons, but a different number of
neutrons.
These are called isotopes
Carbon-14 is an isotope of carbon because it has 2 extra neutrons.
Isotopes are sometimes radioactive
Practice
How many protons?
How many electrons?
How many Neutrons?
Practice 2
How many protons?
How many electrons?
How many Neutrons?
First person to say give me some
homework gets a candy
Elements, Mixtures,
Compounds
Element
A substance is an element if all the atoms are the same color and size and they
behave in the same way.
Compound
A compound is the chemical combination of 2 different elements.
Compound
Elemental chlorine is deadly
Elemental sodium is extremely reactive
When you combine them together in a compound you get table salt.
A compound is always more stable than its ingredients.
Compound
Compounds are pure substances because all parts of the substance are the same
Every molecule will look the same.
Mixtures
Any combination of different elements and compounds is a mixture
A mixture is a physical combination, not a chemical one.
This means that it can be physically separated into its ingredients by
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Filtration
Distillation
Sorting
Heterogeneous Mixture
A mixture that has distinct parts.
Homogeneous Mixture
All parts of a homogeneous mixture are
visually the same. You can’t tell the
strawberries apart from the bananas or the
yogurt.
Common elements, compounds, and mixtures
Elements
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Oxygen
Carbon
Hydrogen
Lithium
Sodium
Compounds
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Salt-NaCl
Water-H2O
Sugar-C6H12O6
Mixtures
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Salt water
Air
Pancake Batter
Salad Dressing
Ways to Draw Atoms
What are the different ways to draw
an atom and its parts?
Bohr Model
The Bohr Model is a way of drawing atoms with its P,E,N
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Find the number of P,E,N
Place protons and neutrons in the nucleus
Place electrons in the proper rings
The number of rings = the row number of the element.
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Row 1=2 electrons max
Row 2=8 electrons max
Row 3=18 electrons max
Valence Electrons
Valence electrons are the electrons farthest
from the center of the atom. Valence
electrons determine how the element
behaves.
Everything in the same family on the
periodic table has the same number of
valence electrons, meaning they behave in
the same way.
Chemical Bond
Valence electrons can be shared or given between atoms. This creates a chemical
bond. Atoms that have a chemical bond are stuck together forming a
molecule/compound.
Valence electrons are only electrons capable of forming bonds with other atoms.
Chemical bonds can only be broken by a chemical reaction
Lewis Dot Structure
Lewis dot structure is a way of drawing atoms, valence electrons, and
compounds.
Chemical bonds
between atoms are
drawn with a dash