The Heating Curve of Water - Jefferson Forest High School

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Transcript The Heating Curve of Water - Jefferson Forest High School

A
phase is a uniform collection of particles.
 Some things can exist in two phases
(milkshakes, slushies, etc.)
 Dynamic equilibrium is a state of a
compound where the particles move
between 2 different states.
 A phase diagram shows the state of a
compound with temperature and pressure.
 Vapor
pressure is the pressure produced by a
liquid or a solid when it is in dynamic
equilibrium with its gas phase and is
measured in mmHg or kPa.
 As temperature increases, vapor pressure
increases and exerts pressure on the walls of
the container.
pressure (atm) -----
Phase Diagram
Melting pt. - liquid and solid
phases at equilibrium
liquid
solid
Boiling pt. - liquid and
gas phase at
equilibrium
gas
0.6
triple point - point at which solid, liquid
and gas phases are at equilibrium
2.6
Temperature (C)
 Heat
of vaporization - the amount of heat
necessary to vaporize a given amount of
liquid.
 The
molar heat of vaporization of water is
40.7 KJ/mol. Therefore 40.7 KJ of energy is
required to vaporize one mole of water.
 Heat
of fusion - amount of heat necessary to
convert a given amount of a solid into a
liquid.
 The
mol
molar heat of fusion for water - 6.00 KJ/
Temperature C -----
Heating Curve for
Water
100
vaporization
heat of vaporization
liquid
melting
heat of fusion
freezing
0
solid
heat added
gas
condensation
 Lab
Activity: Graphing the heating curve for
water

Using the labquest with a temperature probe,
graph the temperature versus time of a sample
of H2O from the solid to the gaseous form