GOAL 3 UNIT C Properties of Water

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GOAL 3 UNIT C Properties of Water
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polar molecule               

• a molecule that has electrically charged areas

• molecule with a slightly positive end and a
  slightly negative end as a result of electrons
  being shared unequally forming an attraction that
  holds the molecules together

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• A water molecule is a chemical bonding of two
  hydrogen atoms with one oxygen atom.

• The bonds which hold the hydrogen and oxygen
  together are called
• covalent bonds.

• A water molecules chemical formula is H2O.

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• The oxygen atom has a
• negative charge.

• The hydrogen atoms have a
• positive charge.

• Water is a polar molecule.

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• The diagrams show a water molecule bonding with
  another water molecule.

• The negatively charged oxygen atom (red) is
  attracted to the positively charged hydrogen atom
  (white) on the other molecule.

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cohesion
attractive force between water molecules that
allows water to form drops and remain a liquid at
room temperatures 
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adhesion               
attractive force between water molecules and
other substances
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Caused by adhesion the water runs along the
glass and does not fall straight.
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capillary action

• the combined force of attraction among water
  molecules and with molecules of other surrounding
  materials

• process that moves water through narrow, porous
  spaces 

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capillary action
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surface tension              
the tightness across the surface of water that is
caused by the polar molecules pulling on one
another
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surface tension              
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surface tension              
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buoyancy             

• the upward force on an object produced by the
  surrounding fluid (liquid or gas) in which it is
  fully or partially immersed 

• the net upward force is equal to the weight of
  the fluid displaced by the object

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Archimedes Principle              
scientific law of buoyancy that states the
buoyant force on an object is equal to the weight
of the fluid displaced by the object
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mass               

• a measure of the amount of matter in an object
  expressed in grams (g)

• a property of an object that is not affected by
  the forces that act on the object

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volume               

• a measure of the amount of space that something
  occupies or the amount of space that something
  contains

• expressed in cubic centimeters (cm3) or
  milliliters (mL) 

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density               

• the ratio of the mass of a substance to the
  volume of the substance (mass/volume)

• expressed as grams per milliliter (g/mL) or grams
  per cubic centimeter (g/cm3)

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DENSITY of WATER               

• The density of water at 0 degrees Celsius (in the
  solid phase) is

0.9150 g/cm3

• The density of water at 4 degrees Celsius (in the
  liquid phase) is

1.0 g/cm3

• The density of water at 100 degrees Celsius (in
  the gaseous phase) is

0.006 g/cm3
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solvent               

• a dissolving agent

• in a solution, the substance that dissolves
  another substance

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universal solvent               
Water is considered to be the universal
solvent.  More substances will dissolve in
water than any other liquid.  This includes
other polar substances (such as sugar) and
ionic compounds (such as salt).    
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universal solvent      
When salt crystals are placed in water, the
slightly positive and negative ends of the water
molecules attract the ions in the crystal.  The
ionic bonds holding the sodium and chlorine ions
together are broken and the ions are pulled
into solution.                                  
                       
ANIMATION Salt Dissolving in Water
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specific heat               
amount of heat energy required to raise the
temperature of 1 kg of a substance by 1 degree
Celsius
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specific heat               
Waters high specific heat ensures slow
temperature changes.
Water can absorb large amounts of heat energy
before it begins to get hot.
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specific heat               
Waters high specific heat ensures slow
temperature changes.
Water releases heat energy slowly when it cools.
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LATENT present but not visible, apparent, or
actualized existing as potential
When a solid substance changes from the solid
phase to the liquid phase, energy must be
supplied in order to overcome the molecular
attractions between the particles of the solid.
This energy must be supplied externally,
normally as heat, and does not bring about a
change in temperature. We call this energy
latent heat (the word "latent" means
"invisible"). The latent heat is the energy
released or absorbed during a change of state.
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latent heat of fusion               
amount of heat energy required to change 1 gram
of water from a solid to a liquid
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LATENT present but not visible, apparent, or
actualized existing as potential
A change of state from liquid to vapor at
constant temperature also requires the input of
energy. This implies that while a liquid
undergoes a change to the vapor state at the
normal boiling point, the temperature of the
liquid will not rise beyond the temperature of
the boiling point. Energy is required to
overcome the molecular forces of attraction
between the particles of a liquid, and bring them
to the vapor state, where these attractions are
minimal.

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latent heat of vaporization               
amount of heat energy required to change 1 gram
of water from liquid into gas
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evaporation               
the process by which liquid water changes into a
gas
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condensation              
the process by which a gas changes into a liquid
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condensation              
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Phases of Water
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Phases of Water
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Phases of Water
gas
solid
liquid
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Phases of Water
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Phases of Water
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LIQUID
GAS
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