Heating Curve of Water

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Heating Curve of Water

• heating curve of water
• Kinetic Energy, Potential Energy and a Heating
  Curve.
• Since Temperature is a measure of "Average
  Kinetic Energy", any change in temperature is a
  change in Kinetic Energy.
• Since temperature does not change during a phase
  change, the energy that is gained or lost is
  Potential Energy.

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E. Changes in State (phase changes) 1. Melting
- solid to liquid a. Substance is absorbing
energy from the surroundings (endothermic)
b. Particles get more kinetic energy and begin
rotating around each other. c. The IFs
begin to weaken (intermolecular forces) to then
form a liquid. d. The energy required to
melt a solid is called the heat of fusion.
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2. Freezing - liquid to solid a. Particles
lose kinetic energy and slow down.
b. Substance releases energy to surroundings
(exothermic) c. IFs b/w particles
become stronger than the particles motion, so
the particles begin merely vibrating in place to
form a solid. d. The amount of heat the
particles must lose to turn into a solid is
called the heat of fusion.
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3. Vaporization - liquid to gas a. Types
1) Boiling - rapid gas bubbles
are produced throughout. 2)
Evaporation - slow occurs at the
surface. b. Liquid particles gain enough
kinetic energy to overcome forces between the
particles and they begin translational motion
this energy is called the heat of vaporization.
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4. Evaporation is a cooling process. a.
Particles in a liquid gain kinetic energy.
b. They leave as gas particles (taking the
energy away with them). c. This leaves less
energy in the liquid, therefore cooling down what
is left.
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5. Condensation - gas to liquid a.
Particles lose kinetic
energy, slow down, and
come closer
together.
b. IFs become strong enough to make
particles merely rotate around each other.
Substance releases energy to surroundings c.
The energy they lose to turn into a liquid is
the heat of vaporization.
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6. Sublimation - solid to gas a. Dry ice -
carbon dioxide b. Iodine c. Frost 7.
During phase changes there is no change of
temperature.
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• Melting/freezing pt occur at same temperature
• Boiling/condensation pt occur at same
  temperature