Thermochemistry 6
Boon Chemistry February 7 & 8, 2013
Catalyst
 Objectives
Make a list of as many things that
can demonstrate my
you can think of that we learned in • Iunderstanding
of heat transfer by
the Temperature and
scoring a 3 or 4 on the Unit 8
exam.
Thermochemistry unit.
In other words, what do you think will
 Agenda
be on today’s exam?
 Catalyst
Use your worksheets and notes as
 Calculations Review
clues.


Group Study
Unit 8 Exam
Exit Slip Review


Compare your exit slip to the example exit slip answers.
On today’s exam, doing all of the following will earn full
credit:

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
Write down the formula/equation you are using.
Plug the correct numbers into the equation.
Use units throughout your work (in the equation and in your
answer).
Find the correct answer.
Multi-Step Thermochemistry Problems

Step 1: Break down the problem into “temperature
change” and “phase change” steps.

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Step 2: Solve the steps separately.

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Use the boiling point and melting point as a guide.
Use q=mcΔT for temperature change and q = mΔHt for phase
change
Step 3: Add up the answers to get the total heat
transferred.

Practice 3: A 150 g piece of aluminum foil is heated from
70 °C to 700 °C. The heat of fusion of aluminum is 398
J/g. The melting point of aluminum is 660 °C. Calculate
the heat transferred to the aluminum.
70°C to 660 °C
Q = (m) (c) ΔT
Q = (150g) (0.897J/g*C) (590C)
Melting 660 °C
Q = (m) ΔH
Q = (150g) (398J/g)
660°C to 700°C
Q = (m) (c) ΔT
Q = (150g) (0.897J/g*C) (40C)
Unit 8 Exam Standards

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(7a) Students know how to describe temperature and
heat flow in terms of the motion of molecules (or atoms).
(7b) Students know chemical processes can either release
(exothermic) or absorb (endothermic) thermal energy.
(7c) Students know energy is released when a material
condenses or freezes and is absorbed when a material
evaporates or melts.
(7d) Students know how to solve problems involving heat
flow and temperature changes, using known values of
specific heat and latent heat of phase change.
Group Study




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Work in a group of 2 or 3 people.
Each student gets a ¼ sheet of paper. You get to use this
on your exam.
Work together to brainstorm what materials to put on
your ¼ sheet.
Use all your notes and worksheets.
You have 15 minutes.
Temperature and Thermochemistry Exam

Expectations/Instructions:


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
The Tools:

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Work independently and silently.
Write on your test.
Be sure to answer every question. There are multiple choice
and short answer.
Use your ¼ sheet.
Use your own calculator.
If you finish early:


Turn in your test and all your unit 8 worksheets, handouts, etc.
Begin the reading assignment for Unit 9: read pp. 576-585 and
answer questions on pp. 585 #1-13.
Homework

Due Monday/Tuesday: read pp. 576-585 and answer
questions on pp. 585 #1-13.