Today Wednesday, June 30, 2004

1
Today Wednesday, June 30, 2004
2
The Mole

• To insert your company logo on this slide
• From the Insert Menu
• Select Picture
• Locate your logo file
• Click OK
• To resize the logo
• Click anywhere inside the logo. The boxes that
  appear outside the logo are known as resize
  handles.
• Use these to resize the object.
• If you hold down the shift key before using the
  resize handles, you will maintain the proportions
  of the object you wish to resize.

• Mr. Chan
• Northwestern University

3
Today (Day 67)

• (0-10) Warmup what is a Mole? Compared to a
  Dozen (slide/overhead)
• (10-20) The Mole and relationships with Chemistry
  - Representative Particles
• (20-25) Practice
• (25-35) Atomic Masses (Elements, Molecules,
  Formula units)
• (35-43) HW Head Start
• The Mole - Extra Credit Molanimals
• Peer Group Ballots

4
The Dynamic Dozen Warmup
5
What is a Mole?

• Set Quantities
• Dozen 12, other quantities
• Mole 6.02 x 1023
• Mole Amount of Substance
• Number of representative particles
• Atoms
• Molecules
• Formula units
• ions
• 1 mole 6.02 x 1023
• Avogadros Number
• Just like previous exercises with conversion
  factors
• Practice 3-6
• Factor Label Method/Dimensional Analysis

6
Determining Masses of Moles

• Atomic Mass
• Atomic mass of element in grams
• Mass of 1 mole of atoms of element
• Molecular Masses
• Add atomic masses of elements
• Also called gram formula mass, molar mass
• Practice 7-10

7
Never too early for Mole Day
8
Today (Day 68)

• (0-15) Discuss HW/Warmup/Review
• Molar Mass of Substance atomic mass, molecular
  mass, formula mass
• (15-30) Mole-Mass conversions
• Mass-Moles (grams to moles)
• Moles-Mass (moles to grams)
• (30-40) Practice
• (40-43) HW Head Start
• Party plans next week
• Peer Groups
• Discuss Tests

9
Conversions Mass and Mole

• 1) Mass to Moles
• 2) Moles to Mass
• Use molar or atomic mass of substance
• Examples
• 1) 72.0 grams Ar, 11.0 grams CH4, 333 grams SnF2
  (?moles)
• 2) 0.720 moles Be, 0.160 mol H2O2, 0.0112 mol
  K2CO3 (?grams)
• Practice 16-19
• A. 0.720 mol Be, 2.40 mol N2, 10.0 mol Cr, 3.32
  mol K, 0.24 mol K2CO3
• B. 5.00 g H2, 0.264 g Ar, 0.370 g B, 11.0 g CH4,
  300 g SnF2

10
Today (Day 69)

• (0-15) Discuss HW/Warmup/Review
• 187 g Al (?moles)
• 2.40 mol N2 (?grams)
• (15-20) Demo (5 min)
• (20-30) Moles and Gases, STP, Gas Density
• (30-35) Practice
• (35-43) HW Head Start

11
Converting Moles and Volumes

• STP Defined
• Specific conditions for experiment
• Standard Pressure and Temperature
• 0 degrees Celsius
• 1 atm or 101.3 kPa
• At these conditions, 1 mole of any gas has a
  volume of 22.4 L
• Also called Molar Volume
• Not equal masses, but 1 mole of each will have
  equal volumes
• Density of a gas expressed in grams/Liters
• Practice 20-23
• Volume at STP 0.960 mol CH4, 3.70 mol N2
• Moles at STP in 67.2 L SO2, 0.880 L He

12
Today (Day 70)

• (0-10) Discuss HW/Warmup/Review
• (10-15) Demo
• (15-25) Unit Conversions, Mole Map
• (25-43) Whiteboards
• (0-43) Mole Bingo

13
Mass-Moles-Molecules-Atoms or Mass-Moles-Atoms
14
Today (Day 71)

• (0-15 min) Discuss HW/Review
• (15-35) Quiz
• (35-43) HW EC

15
Today (Day 72)

• (0-10) Review Quiz/Warmup
• Assuming STP, calc volume of gases 0.0032 mol
  CO2
• Assuming STP, calc moles of gases 100 L C2H6
• (10-25) Percent Composition
• (25-35) Practice/HW Head Start
• (35-43) Discuss Lab
• (0-43) Molar Stations Activity

16
Calculating Percent Composition

• Recall Oreo vs. DoubleStuff, demo w/ hydrates?
• What is Percent Comp?
• Relative amounts of each element
• Using Experimental Data
• Percent of element grams of element divided by
  grams of compound x 100
• Examples
• 9.03 g Mg with 3.48 g N
• 29.0 g of Ag combines with 4.30 g of S
• 222.6 g of Na combines with 77.4 g of O
• Using chemical formula to calculate percent comp
• Percent of element grams (atomic mass) element
  divided by grams (molar mass)of compound x 100
• Examples
• Ethane, C2H6
• Hydrogen cyanide, HCN
• Water, H2O
• Using comps to determine masses
• Can calculate the amount of a particular element
  if given mass of total compound
• Examples (Calc Hydrogen)
• 350 g C2H6

17
Today (Day 73)

• (0-10) Opening Ceremonies
• Demo Methane Bubbles
• (10-30) MOLympic Games
• (30-35) Happy Holidays!

18
Today (Day 74)

• IceBreaker (0-10)
• First/Last initial with Word from Break
• Warmup/Review (10-25 min)
• What is a mole?
• Number of molecules in 2.5 moles of CO?
• Molecular mass of CO2
• Number of moles in 100 grams of CO2
• Significance of 22.4 L
• Number of atoms in 100 grams of CO2
• Percent Composition of CO2
• Percent Composition
• 8.20 g Mg with 5.40 g O
• C3H8
• Mass of carbon in 82.0 g C3H8
• Emp.Formulas and Molecular Formulas (25-43 min)
• Molar Stations Completion (Regular)

19
Determining Empirical and Molecular Formulas

• What are Empirical Formulas?
• Lowest whole number ratio of atoms of elements in
  a compound
• May or may not be molecular formula
• Determining Empirical Formulas
• Percent to Mass, Mass to Mole, Divide by Small,
  Multiple Until Whole
• Examples
• 25.9 N, 74.1 O
• 94.1 O, 5.9 H
• 67.6 Hg, 10.8 S, 21.6 O
• 17.6 Na, 39.7 Cr, 42.7 O
• Determining Molecular Formulas
• Some empirical formulas can be doubled, tripled,
  or multiplied to make formulas that are different
  compounds
• Multiply empirical formula by whole number
• Examples
• CH4N with molecular mass of 60g
• C2HCl with molecular mass of 181.5g
• 58.8 C, 9.8 H, and 31.4 O with molecular mass
  102 g/mol
• Practice 35-38

20
Today (Day 75 or 76)

• (0-10) Warmup/Discuss HW
• (10-15) Introduce Project
• (15-20) Intro Lab
• (20-43) Lab OR Begin Review WS/ Grades/Missing
  Work
• (0-43) Lab
• Discuss Lab Data

21
Lab Combining Ratios of Calcium and Chlorine

• React pure Calcium with HCl (source of Chlorine)
• Determine the chemical formula experimentally
• Atom ratios vs. Weight ratios
• Introduction to Bunsen Burners
• Goggles at all times in lab area
• Collect data on cover sheet
• Analysis of data tomorrow

22
Today (Day 75 or 76)

• (0-10) Warmup/Review
• (10-43) Ch. 6 Review Packet
• Discuss Lab Data

23
Today (Day 77)

• (0-10) 1Question Review/Project Idea/Check in
  Syllabus
• (10-43) Weakest Link Review MC questions
• (0-43) Computer Lab Review Projects

24
Today (Day 78)

• Test Chapter 6
• Check Syllabus

25
Today (Day79-80)

• Computer Lab

26
Today (Days81-83)

• Final Exam Review
• Project Presentations

27
(No Transcript)