AP Physics Heat Capacity Lab

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AP Physics Heat Capacity Lab
Objective : The objective of this lab exercise is to use calorimetry as
well as the concepts of heat capacity and exchange to determine the
identity of two unknown metals objects.
Experimental Procedure [ bear in mind you
may need to add more detail or even steps ]
• 1] With two unknown objects completely submerged in water, heat the water
to a vigorous boil
• 2] Measure temperature of boiling water – this is also initial temperature of
unknown objects before transferring to cold water
• 3] Have cold water handy ( poured from an ice bath – but only use the water as
we want to keep this simple and ice does not have the same specific heat
capacity value as water ) and pour a certain volume of this water into the inner
cup of a calorimeter
• 4] Measure temperature of cold water inside calorimeter – this is your initial
temperature of the cold water before adding hot objects
• 5] Remove one hot unknown object from boiling water, shake water off of it
briefly, then add to cold water in calorimeter
Experimental Procedure [ bear in mind you
may need to add more detail or even steps ]
• 6] Measure equilibrium temperature of cold water plus unknown object
• 7] Repeat steps for unknown object #2
• 8] measure the mass of each unknown object, dry
Analysis Procedure [ bear in mind you may
need to add more detail or even steps ]
• 1] Using the known value of the specific heat capacity of water, calculate how much
heat was transferred to the cold water from each hot object, separately
• 2] The amount of heat found in step 1] is the same amount of heat that the unknown
object lost
• 3] Knowing this as well as the relevant temperature change and the unknown’s mass,
the specific heat capacity of each unknown can be calculated
• 4] If you conducted these measurements more than once, average the values [ I
know AJ I told you different but have changed my mind ] but bear in mind you may
not want to use the average when comparing your values to the literature
• 5] Compare these numbers to values in a table of known specific heat capacities and
try to decide what material each of the unknowns is made of
• Having an average specific heat capacity may or may not lead you to a confident answer so you
may need to compare your measured specific heat capacity values from each trial separately
Questions ( Discuss in “Conclusion” )
• What types of error may have occurred during this lab ( more detail
than “human error” )?
• If you were to conduct this experiment again, how could you improve
on your accuracy?
• If you find compare your experimental values to a table other than
that in the text, cite the source ( website, etc. )
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