Exam 1

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Exam 1

• Tuesday 9/29 610-800 pm CHEM 1650
• Bring a non-programmable calculator
• You will be provided the last two pages of the
  course pack
• Practice problems posted on website
• Exam ethics

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Exam Topics

• Through lab TOMORROW
• Homework answer key posted
• Scientific definitions (fact, law, etc.)
• Scientific method
• Unit conversions significant figures
• Mole
• Atoms (historical experiments, subatomic
  particles, size, orbitals, electron
  configurations)
• Elements, molecules
• Periodic table (trends)

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Next Chemical Scholarship Assignment

• Work in new group
• Presented in Section on Wednesday 10/5
• Briefing on chemically modified food
• Goals
• Explore use of chemistry in food
• Tie examples to class topics
• Determine most controversial and most beneficial

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Topics

• Trans fats
• MSG
• Nitrates
• Homogenized milk
• Vitamin D in OJ
• Fluoride in water
• Fortified flour
• Iodized salt

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Brief

• What is the modification (chemical structures as
  appropriate)
• Why it is done?
• How it the food modified?
• What food products does it appear in?
• Tie in some aspect of this chemistry course
  (elements, periodic trends, bonding,
  intermolecular forces, thermochemistry)
• A brief history (how, when, and where did it all
  get started?)
• Is it FDA approved?
• Summarize the modification advantages and
  disadvantages
• Brief us on any debate surrounding the
  modification (explain the positions that people
  hold and why they hold them). How heated is the
  debate?
• Cite data from at least one scientific study

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Misc.

• 7 minutes total
• Whos talking?
• Background
• Debate
• Answers to questions
• Questions
• Power point available

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Grading (20 points)

• 4 points (what, how, where, when)
• 4 citations including scientific study and
  results
• 4 debate
• 2 tie to chemistry studied in class
• 2 (1 point each) question answered
• 2 (1 point each) question asked
• 2 presentation (volume, clarity, effectiveness)

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Exam 2

• Tuesday, October 25 610-800 pm CHEM 1650
• Lewis structures VSEPR
• Bonding Polarity Intermolecular forces
• Thermochemistry
• Calorimetry
• Phase change
• Heats of formation enthalpy of reactions
• Aqueous Solutions
• concentration units
• colorimetry
• precipitation

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Group Evaluations

• September (everyone got 9 in-class points)
• October
• Total points out of total possiblefood briefing
  grade (9/9)
• Returned today in discussion
• Note 75 possible in-class points to date

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Exam 2
Range 15.5-38.5 Mean 27.5 Median 28.5
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If assigning grades..

• Slide down a grade
• A 550/700
• B 475/700
• C 400/700
• D 325/700

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Intermolecular Forces
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Lewis Structures

• Common answers

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Thermochemistry

• Heat out of ice
• Water 21.3 to 0oC
• Water to ice (heat of fusion)
• Ice 0.0 to 22oC
• How much propane would you have to burn to get
  the same amount of heat
• C3H8 5O2 ? 3 CO2 4 H2O
• What is DH of reaction?
• kJ/mol C3H8 to grams C3H8

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Team problem

• qice - qbeer
• qice Melt ice raise temp of water
• qbeer 6 bottles ethanol water