What Do We Need to Know

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What Do We Need to Know?

• Matter

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chemically
Combine
Not
Two or more substances not chemically combined.
When atoms of more than one element chemically
combine they form a compound.
Substances made of only one type of atom.
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How Does it Work?
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Chemical Property

• Describes a change that occurs when one substance
  reacts with another substance.
• Example A chemical property of water is that it
  will separate into hydrogen and oxygen when an
  electrical current is passed through it.

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Orbital Basics Check This Out Click Below
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Bonding

• The force that holds atoms in compounds together.
• When two molecules share or lend an electron,
  they are joined in a chemical bond.

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Ions

• Electrically charged atoms are ions.

Ions are attracted to each other when they have
opposite charges.
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Example
Oxygen (O) and fluorine (F) are two good
examples. Each of those elements is looking for a
couple of electrons to make a filled shell. They
have one filled shell with two electrons but
their second shell wants to have eight. There are
a couple of ways they can get the electrons. (1)
They can share electrons, making a covalent bond.
Or (2) they can just borrow them, and make an
ionic bond (also called electrovalent bond).
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Metallic Bonds

• Electrons are free to move from one ion to the
  other.
• Found in metals such as copper, gold, aluminum,
  and silver.
• Give metals the ability to conduct electricity.

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Hydrogen Bonds

• Form when the positive end of one molecule is
  attracted to the negative end of another
  molecule.
• Form without the interaction of electrons.
• Responsible for the property of cohesion allows
  water to form raindrops.
• Hydrogen bonds are easily broken.

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Hydrogen Bonding in Water
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Mixture

• Heterogeneous Mixture components not mixed
  evenly each component retains its own
  properties.
• Homogeneous mixture compounds evenly mixed
  cant see each component also called solutions.

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IsotopesAtoms that have the same number of
protons but different numbers of neutrons are
called isotopes.
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Remember

• The components of a mixture can be separated by
  physical means.
• The components of a compound must be separated by
  chemical means.

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Properties of Matter

• Physical Properties properties that you can
  observe without changing a substance into a new
  substance.
• Density an objects mass divided by its volume.
• Density is measured using grams per cubic
  centimeter (g/cm )
• An object less dense than water will float in
  water.

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Four physical properties of Matter

• Solids the matters atoms are in a fixed
  position relative to each other.
• Liquids atoms are attracted to each other, but
  can change positions with each other.
• Gases atoms have almost no attractive force on
  each other, so atoms move freely and will fill
  the entire container where they are placed.
  Plasma electrons can escape and move outside of
  the ions electron cloud.

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Matter Can Change from one State to another

• Changes in state occur because of temperature or
  pressure change.
• Matter is changed from a liquid to a solid at its
  freezing point.
• Matter is changed from a liquid to a gas at its
  boiling point.
• When matter changes state, its chemical
  properties do not change, but physical properties
  may change.

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Phases of Water

• Animation
• Phases of Matter