Chapter 16 Notes II
Calorimetry
What is calorimetry?
• Essentially, the science of
measuring heat change.
• Using the specific heat of
something you know to
find the specific heat of
something you don’t.
What is calorimetry?
• It takes advantage of
the law of conservation
of energy.
• The principal shows
that heat lost by one
substance has to equal
heat gained by another.
When a hot object is put into
cool water what happens?
Object
at 100oC
50g
Final
temperature
of both is
22oC
250g
50g
Water at
20oC
NOTICE:
Heat lost is equal to
heat gained, but
temperature lost
does NOT equal
temperature gained
So, to find the specific heat of
the object…
•Solve q=mCDT for
heat gained by water
THEN
•Use q you found to
solve q=mCDT for the
specific heat of the
object.
Calorimeters
• A calorimeter is a
device that measures
heat change.
• It can be extremely
sophisticated, or as
simple as two foam
cups, a thermometer
and water!
Ghetto KPHS Style Calorimeter
Bomb Calorimeter
Practice Problem #1
• What is the specific heat
of a metal if a 50.8g
sample at 100.0oC raises
the temperature of 258.2g
of water from 25.2oC to
28.1oC?
Practice Problem #2
• What is the specific heat
of a substance if a 22.6g
sample at 104.5oC raises
the temperature of 125.3g
of water from 22.6oC to
33.1oC?