Atoms, Compounds, and Mixtures

1
Atoms, Compounds, and Mixtures

• Ch. 1 Sect. 3

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Chemistry

• Chemistry is the study of the composition and
  properties of matter.
• Everything in our world is either matter or
  energy.
• Light is an example of energy.
• Everything in our entire world is made of atoms.
• When atoms are bonded together, they are called
  molecules or compounds.
• Sometimes atoms exist un-bonded to other atoms.

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Atoms

• There are different types of atoms, each type is
  an element.
• To the right are different elements.

Helium
Sodium
He
Na
Gold
Carbon
Au
C
Chlorine
Cl
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Compound / Molecule
Sodium chloride is table salt, which is

• I use these terms interchangeably.
• Two or more atoms or ions bonded together.
• You will learn what ions are later.
• To the right are different compounds or molecules.

Sodium
Chlorine
Na
Cl
H
Methane
H
C
H
H
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Diatomic Molecule

• A molecule made of two atoms of the same element.
• There are 7 elements that exist in nature as
  diatomic molecules
• Hydrogen
• Nitrogen
• Oxygen
• To the right are examples of diatomic molecules.

Chlorine gas
Cl
Cl
Hydrogen gas

• Fluorine
• Chlorine
• Bromine
• Iodine

Oxygen gas that we breathe.
H
H
O
O
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Diatomic Molecule

• A molecule made of two atoms of the same element.
• There are 7 elements that exist in nature as
  diatomic molecules
• Hydrogen
• Nitrogen
• Oxygen
• To the right are examples of diatomic molecules.

Chlorine gas
Cl
Cl
Hydrogen gas

• Fluorine
• Chlorine
• Bromine
• Iodine

Oxygen gas that we breathe.
H
H
O
O
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Mixture

• Two or more atoms or ions together but NOT
  bonded.
• To the right is one example of a mixture.

H
H
Cl
Na
H
C
H
Na
Cl
C
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Mixture
H

• OR
• Two or more compounds NOT bonded but at the same
  location.
• To the right is another example of a mixture.
• Salt water.

H
O
Na
Cl
H
H
O
Na
Cl
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Mixture
Na
H

• OR
• Compounds in the same location as atoms but NOT
  bonded to them.
• To the right is another example of a mixture.

H
O
Na
Na
Na
H
H
O
Na
Na
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Pure Substance

• If a substance is not a mixture, then it is a
  pure substance.

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Alloys

• A mixture of only metals.
• Examples of alloys
• 14-karat gold gold zinc silver
• Only 24-karat gold is pure gold
• Steel Iron nickel, chromium, and/or tungsten
• Bronze copper tin
• All of these popular examples of alloys are
  stronger than each individual metal that they are
  made of.
• This is not true of all alloys.

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Natural vs. Synthetic

• Synthetic
• Any substance that exists because a person has
  made it.
• Examples
• Spenda
• Polyester
• Nylon
• Pharmaceutical
• products

• Natural
• Any substance that exists without mans actions.
• Examples
• Sugar
• Cotton
• Wool
• Herbal remedies

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Homework

• Pure Substance vs. Mixtures WS
• P. 9 1,2
• Study for Unit 1 Quiz 1
• Friday at the beginning of class.