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Chemistry
Rev 012312
A singularity expanded rapidly to form the beginnings of our universe. The universe began to cool and the
wavelengths of light became too long for us to see. And so the universe
appeared black.
Soon, particles began to form.
Quarks and electrons, and eventually protons and neutrons.
Eventually glowing clouds of hydrogen gas form, along with young stars.
Eventually glowing clouds of hydrogen gas form, along with young stars.
You are here
Galaxies form
A small yellow star in the corner of the Milky Way Galaxy develops a following of rocky planets and gas giants.
One planet in particular exhibits the potential for life.
It has water and eventually develops oxygen
Earth is in the Goldilocks spot.
Everything is “just right” for …Everything is “just right” for …
Chemistry
Life abounds
Scientists have found complex chemical compounds throughout the universe.
Chemistry
everything in the universe
is all about
Everything in the universe
MatterEnergy
is either
or
Matter
Energyand
are equivalent
E=mc2
MatterEnergyE=mc2
MatterEnergyE=mc2
Chemistry
MatterIs anything that
has mass, and takes up space.
Matter
Physical Properties
Chemical Properties
Chemical Properties
… are all about chemical changes
2 H2(g) + O2(g) 2 H2O(g)
Chemical Properties2 H2(g) + O2(g) 2 H2O(g)
Hydrogen and oxygen are stored in the external fuel tank.They react to produce water vapor, which exits at the nozzles.
Chemical Properties3Al(s) + 3NH4ClO4(s)
In the solid rocket boosters (SRB’s) aluminum metal reacts with ammonium chlorate.
Al2O3(s) + AlCl3(s) + 3NO(g) + 6H2O(g)
Chemical Properties3Al(s) + 3NH4ClO4(s)
And of course, heat is released.
Al2O3(s) + AlCl3(s) + 3NO(g) + 6H2O(g)
Most chemical changes are accompanied by energy changes.
Chemical Properties
Flammability
… are those that influence the way substances react to form new substances.
Acidity
Reactivity
Physical Properties… are things we can measure….
mathematically
Physical PropertiesMass
VolumeDensity
Melting pointBoiling point
Physical properties are things we can quantify.
V
mD
ColorOdor
HardnessMalleability
Ductility
Specific heat capacity
Physical Properties
Conductivity
Solubility
There is a fine line between chemical changes and physical properties.
Many physical properties involve chemical changes.
The value of the solubility of a salt is a physical property, but the process of dissolving is a chemical change.
Matter… has three physical states
solidliquid
gas
Changes in the physical state involve subtle chemical changes.
solidliquid
gas
Energy is absorbed or released as intermolecular bonds are broken or formed.
solidliquid
gas
The degree to which the molecules interact determines if a substance is a solid, liquid or gas.
solidliquid
gas
In a solid, the molecules are close together in an orderly arrangement, with very high intermolecular attraction.
solidliquid
gas
In a liquid the molecules are farther apart but move about in a random fashion, with a high degree of attraction.
solidliquid
gas
In a gas, the molecules are much farther apart, move randomly, with very little attraction between molecules.
solidliquid
gas
Mattercan be classified as either a
mixture
pure substanceor
pure substanceHas definite composition.
Compoundsor
Elements
An element is one of the basic building blocks of nature.
There are 88 to 90 naturally occurring elements.
An element is one of the basic building blocks of nature.
Elements are distinguished by the different numbers of
protons in their nuclei.
Elements are represented by symbols.
HN
OC
NeAl
FeU
Compounds are represented by groups of symbols.
NaCl H2O
C12H22O11
Fe2(SO4)3
A compound is the chemical combination of
two or more atoms.
Compounds have a definite composition.
Water is the same everywhere in the universe.
Water is always H2O.
There are no water molecules anywhere with a different composition.
Water is H2O. Hydrogen peroxide is H2O2 and OH is the hydroxyl radical.
They contain the same elements, but in different ratios.
Water, hydrogen peroxide and the hydroxyl radical all have different chemical and physical properties.
Water is H2O. Hydrogen peroxide is H2O2 and OH is the hydroxyl radical.
Demo: To two beakers each containing a solution of KMnO4, add equal amounts of water to one and H2O2 to the other.
To the solution of KMnO4 and water, add H2SO4 and then add H2O2, preferably on a magnetic stirrer.
What are some other elements that you are familiar with?
Do you know any more formulas for
chemical compounds?
mixtureComposed of two or more pure substances with no definite composition.
Describe something that is a mixture.
mixtureheterogeneous
homogeneous
See the individual components
Appears to be uniform
A solution is a homogeneous mixture.
A solution contains a solute and a solvent.
The solute is what is dissolved …. sugar.
The solvent is what does the dissolving - …..water.
Sugar and water are both pure substances.
C12H22O11 and H2O
They each have their own definite composition.
Sugar and water are both pure substances.
C12H22O11 and H2O
They can be mixed in almost any proportion to make a solution.
A solution is a homogeneous mixture that is uniform throughout.
Once dissolved, you won’t be able to see the sugar in the solution.
But unlike a compound, the mixture can be easily separated back into water and sugar.
Suggest a method for doing that.
But the water and sugar themselves cannot be separated into the elements by physical means.
To do that requires…
Chemistry
Let’s review
How are matter and energy related?
Matter
Energyand
are equivalent
E=mc2
How do we describe matter?
MatterIs anything that
has mass, and takes up space.
What does matter consist of?
MatterConsists of atoms
which combine to form molecules.
What are some properties of mater?
Matter
Physical Properties
Chemical Properties
Chemical Properties… are those that influence the way substances react to form new substances.
Flammability Acidity
Reactivity
Physical Properties… are things we can measure….
mathematically
What are some physical properties?
Physical PropertiesMass
VolumeDensity
Melting pointBoiling point
Phase changes are subtle chemical changes.
V
mD
ColorOdor
HardnessMalleability
Ductility
Specific heat capacity
Physical Properties
Conductivity
Solubility
What are pure substances?
pure substanceSomething that cannot be broken into simpler substances by physical means.
Compoundsor
Elements
What is a mixture?
mixtureComposed of two or more pure substances with no definite composition.
mixtureheterogeneous
homogeneous
See the individual components
Appears to be uniform
A solution is a homogeneous mixture.
What is a solution?
A solution contains a solute and a solvent.
The solute is what is dissolved - sugar.
The solvent is what does the dissolving - water.
A solution is a homogeneous mixture that is uniform throughout.
Once dissolved, you won’t be able to see the sugar in the solution.
What is the study of matter and energy and the connection between the two?
Chemistry
Copyright 2012Mike Jones
Pisgah High SchoolCanton NC 28721All rights reserved.