Thursday, Oct. 29th:

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(No Transcript)
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Friday, Nov. 2nd A DayMonday, Nov. 5th B
DayAgenda

• Homework Questions/problems
• Sec 10.4 Quiz Order and Spontaneity
• Lab Discussion/write-up Calorimetry and
  Hesss Law
• Movie Heat
• Concept review work time
• Lab next time dress appropriately!

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Sec. 10.4 reviewPg. 367 3-5, 7-11

• Questions?
• Problems?
• Hand in

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Sec 10.4 QuizOrder and Spontaneity

• You can use your notes, your book, and a lab
  partner of your choice to complete the quiz
• Good Luck!
• Pick up a copy of the lab when you hand in your
  quiz and start reading it through

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Calorimetry and Hesss LawDiscussion

• Remember, Hesss Law states that we can find the
  enthalpy change for a reaction by adding up the
  enthalpy changes for the individual steps.
• You will run 3 different reactions
• NaOH (s) H2O (l)
• NaOH (aq) HCl (aq)
• NaOH (s) HCl (aq)
• (The 1st 2 reactions add up to give the 3rd)

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Calorimetry and Hesss LawDiscussion

• You will use the calorimetry equation
• q mC?T to calculate the heat released in each
  reaction.
• You will then use stoichiometry and the
  calorimetry equation to calculate find out if the
  temperature did indeed get hot enough to burn the
  man.

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Calorimetry and Hesss LawPurpose

• What is the purpose of this lab?
• The purpose of this lab is to measure the amount
  of heat released by mixing NaOH and HCl to find
  out if enough heat is released to raise the
  temperature high enough to cause a burn.

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Calorimetry and Hesss LawMaterials

• There are a few changes to the materials list
• We will NOT be using the 3 items listed under
  Optional Equipment
• We will be using calorimeters, NOT plastic foam
  cups
• You will use a porcelain scoop instead of forceps
  when handling the NaOH.
• Changes to material list have already been made!

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Calorimetry and Hesss LawProcedure

• The procedure for this lab is a little confusing
  because the original lab handout showed 2
  different ways of running the lab.
• Your procedure starts on the top of pg. 36 where
  it says Advance Preparation, steps 1 and 2.
• The rest of page 36 is crossed out because you
  will be using the Thermometer Procedure that
  begins on pg. 39.

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Lab Discussion Calorimetry and Hesss Law

• There are 3 different reactions you will be
  running, all using hydrochloric acid (HCl) and
  sodium hydroxide (NaOH).
• You do not have to wear gloves when handling the
  NaOH, but you must use the porcelain scoop to
  measure them. Do not touch the pellets!
• Be sure to CLOSE the NaOH container when done
  measuring it because it is hygroscopic , meaning
  it will absorb moisture from the air and gain
  mass.

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Lab Discussion Calorimetry and Hesss Law

• When you add the chemicals to the calorimeter,
  make sure you add them to the beaker and NOT
  directly into the metal calorimeter container.
• These chemicals are corrosive and will pit the
  metal calorimeters.
• The actual laboratory part of this lab is not
  difficult, its the calculations that will take
  some time.
• We will go through the calculations
• together back in the classroom.

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Lab Write-Up Calorimetry and Hesss Law

• Be sure to update your table of contents with
  this lab.
• You have the rest of the period to complete the
  lab write-up with your lab partner
• Title
• Purpose
• Hypothesis
• Materials
• Procedure
• Reflection Statement

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Movie Heat

• You DO NOT have to take
• notes on the movie, but I do
• expect you to pay attention!