Your SlideShare is downloading. ×
0
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Ch 1
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Ch 1

373

Published on

Chapter 1 notes

Chapter 1 notes

0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
373
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
6
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Welcome to Chemistry! Michael Spath
  • 2. Class Format <ul><li>Lectures start promptly at 5:45 and end no later then 6:45 </li></ul><ul><li>I will be available after class for questions </li></ul><ul><li>I will not read the book to you </li></ul><ul><li>I expect you to have read the material BEFORE class </li></ul><ul><li>Follow the guidelines in the syllabus </li></ul>
  • 3. Contacting Me <ul><li>Email: [email_address] </li></ul><ul><li>I will get back to you within a day </li></ul>
  • 4. Absence <ul><li>All homework, quizzes, and tests are due as specified on the syllabus unless you make arrangements with me BEFORE hand </li></ul><ul><li>If you have a fever, sore throat, and cough (i.e., the flu) DO NOT come to class until your temperature has been normal for one day </li></ul>
  • 5. Absence (Cont.) <ul><li>I will make every accommodation to keep you current during your illness </li></ul><ul><li>DO NOT catch the flu more then once </li></ul>
  • 6. Have Fun!
  • 7. Homework Assignment 1 Due 9/21/2009 <ul><li>SHOW ALL WORK </li></ul><ul><li>CH1 </li></ul><ul><ul><li>1.12, 1.28, 1.32, 1.40, 1.44 </li></ul></ul><ul><li>CH 2 </li></ul><ul><ul><li>2.18, 2.26, 2.44, 2.60, 2.90 </li></ul></ul>
  • 8. Chapter 1 <ul><li>Why Chemistry? </li></ul><ul><li>How does Chemistry affect you? </li></ul><ul><li>Think about </li></ul><ul><ul><li>Electronics (semi-conductors) </li></ul></ul><ul><ul><li>Medicine </li></ul></ul><ul><ul><li>Energy </li></ul></ul>
  • 9. Matter <ul><li>Mass (NOT weight) </li></ul><ul><li>Space </li></ul><ul><li>Three states </li></ul><ul><ul><li>Solid </li></ul></ul><ul><ul><li>Liquid </li></ul></ul><ul><ul><li>Gas </li></ul></ul>
  • 10. Types <ul><li>Elements (117 of them) </li></ul><ul><ul><li>CAN NOT be broken down chemically </li></ul></ul><ul><ul><li>CAN be combined to make compounds </li></ul></ul><ul><li>Compounds </li></ul><ul><ul><li>Made of elements </li></ul></ul><ul><ul><li>Can be broken down or rearranged by chemical means </li></ul></ul><ul><ul><li>Always have the same ratio of elements (law of definite proportions) </li></ul></ul><ul><ul><li>Properties of compounds are different then those of their constituent elements. </li></ul></ul>
  • 11. Definite Proportions <ul><li>Water: 1 Oxygen to 2 Hydrogen </li></ul><ul><li>Ammonia: 1 Nitrogen to 3 Hydrogen </li></ul>
  • 12. Mixtures <ul><li>Do not have definite proportions </li></ul><ul><ul><li>Coffee – 1 sugar or 2? Milk or cream? </li></ul></ul><ul><li>Can be Homogenous or Heterogeneous </li></ul><ul><li>Homogenous – the same everywhere in the sample (salt water) </li></ul><ul><li>Heterogeneous – varies from point – to – point (M&Ms and mixed nuts) </li></ul>
  • 13. Solutions <ul><li>Homogenous </li></ul><ul><li>Can be either liquid, solid, or gas. </li></ul><ul><ul><li>Soda has a gas dissolved in a liquid </li></ul></ul><ul><ul><li>Metallic alloys (the crystalline ones) are solids “dissolved” in solids </li></ul></ul>
  • 14. Properties of Matter <ul><li>Physical – describe what the substance or mixture is like (color, temperature, hardness) </li></ul><ul><li>Chemical – describe how the substance reacts with other substances </li></ul><ul><li>Specific to an element or compound. If the compound is changed chemically, the properties change (burn gasoline and the clear liquid becomes CO 2 and water </li></ul>
  • 15. Properties of Matter <ul><li>Intensive Properties – do not depend on the amount of material (density, reactivity, conductivity, magnetic response) These are what we use to identify elements and compounds </li></ul><ul><li>Extensive Properties – based on the amount of material (mass, volume, length) </li></ul>
  • 16. Separation of Mixtures <ul><li>Chemical Engineers take 3 different semester long classes on separation processes </li></ul><ul><li>Separation method depends on the physical properties of the material </li></ul>
  • 17. Separation of Mixtures <ul><li>Solids & Liquids are separated by filtration (sink trap), centrifugation (spin cycle), or settling. </li></ul><ul><li>Solutions are separated by distillation </li></ul><ul><ul><li>Simple distillation like boiling off water from salts or other solids </li></ul></ul><ul><ul><li>Multi-stage distillation for liquid – liquid separation (gasoline, alcohol ala Jim Beam) </li></ul></ul><ul><ul><li>Multi-stage means that it’s done over and over, each stage getting a little closer to the target. </li></ul></ul>
  • 18. Separation of Mixtures <ul><li>Uranium 235 - 238 separation by the US 1940 – 1945 (Manhattan Project) </li></ul><ul><ul><li>Mass spectroscopy – multi stage (push ionized gaseous U by a strong magnet the heaver 238 does not go as far as the 235) this fed… </li></ul></ul><ul><ul><li>Multi stage gas centrifuges – each one produced a gas that had slightly more 235 </li></ul></ul>
  • 19. Units of Measurement <ul><li>British (what we use) </li></ul><ul><ul><li>Temp – Deg. Fahrenheit or Rankin </li></ul></ul><ul><ul><li>Length – Inches, Feet, Miles </li></ul></ul><ul><ul><li>Mass – Pounds </li></ul></ul><ul><ul><li>Force – Pounds (they are DIFFERENT and easy to confuse) </li></ul></ul>
  • 20. Units of Measurement <ul><li>Metric or SI (what everyone else uses) </li></ul><ul><ul><li>Temp – Deg. Celsius or Kelvin </li></ul></ul><ul><ul><li>Length – Meters </li></ul></ul><ul><ul><li>Mass – Grams </li></ul></ul><ul><ul><li>Force – Newtons (not the fig type) </li></ul></ul><ul><li>Base vs Derived – Derived units are calculated from base units </li></ul>
  • 21. Why Rankin and Kelvin <ul><li>They start at ZERO </li></ul><ul><ul><li>Celsius starts at -273.15 o C, F at -460 o F </li></ul></ul><ul><ul><li>Don’t use degrees with Rankin & Kelvin </li></ul></ul><ul><li>If you try to do any thermodynamic calculation in C or F (the gas law problems you will be doing) and you will get a very wrong answer. </li></ul>
  • 22. Units of Measure <ul><li>Base & Derived Units </li></ul><ul><li>Base units are like elements, they can not be broken down any further. </li></ul><ul><li>Derived units are like molecules, they are made up of one or more base units </li></ul>
  • 23. Units of Measure <ul><li>Base units </li></ul><ul><ul><li>Length </li></ul></ul><ul><ul><li>Mass </li></ul></ul><ul><ul><li>Time </li></ul></ul><ul><ul><li>Temperature </li></ul></ul><ul><ul><li>Charge (electrical) </li></ul></ul><ul><li>Derived units </li></ul><ul><ul><li>Volume (length 3 ) </li></ul></ul><ul><ul><li>Density (mass / volume </li></ul></ul><ul><ul><li>Speed (length / time) </li></ul></ul><ul><ul><li>Force (mass*length / time 2 ) </li></ul></ul><ul><ul><li>Pressure (force/lenght 2 ) </li></ul></ul><ul><ul><li>Current (charge / time </li></ul></ul>
  • 24. Mass and Weight <ul><li>Mass is the AMOUNT of something present in a sample. </li></ul><ul><li>Weight is the force gravity exerts on the sample. F=MA </li></ul><ul><li>In space, objects are weightless, NOT mass less. If two space ships collide, they still break. </li></ul>
  • 25. Conversions <ul><li>Rules of algebra apply: </li></ul><ul><ul><li>A fraction whose numerator and denominator are the same equals one </li></ul></ul><ul><ul><li>Any number times one equals that number </li></ul></ul><ul><li>Units of measure ARE included </li></ul><ul><li>Our goal is to make a fraction that will cancel the unwanted unit and leave the desired one </li></ul>
  • 26. Conversions <ul><li>To make life easier, my classmates and I would always convert everything to SI units, even if the problem was given with all British units and we had to convert our answers back to British in the end. The harder the problems get, the more sense it makes to use SI </li></ul>
  • 27. Conversion Example <ul><li>Convert 2. feet into millimeters </li></ul><ul><li>2. feet * 12 inches * 2.5 cm * 10 mm </li></ul><ul><li>1 foot 1 inch 1 cm </li></ul><ul><li>600 mm </li></ul>
  • 28. Conversion Example 2 <ul><li>Convert 3. kg to stone </li></ul><ul><li>3. kg * 1.6 stone 4.8 stone </li></ul><ul><li>1 kg </li></ul>
  • 29. Conversion Example 3 <ul><li>Temperature </li></ul><ul><li>Absolute Zero is the absence of heat and all atomic and molecular movement stops. </li></ul><ul><ul><li>-273.15 o C </li></ul></ul><ul><ul><li>-460. o F </li></ul></ul><ul><ul><li>0 K </li></ul></ul><ul><ul><li>0 R </li></ul></ul>
  • 30. Conversion Example 3 <ul><li>o C= 5/9 ( o F-32) o F=9/5 o C+32 </li></ul><ul><li>Convert 72 o F to Kelvin </li></ul><ul><li>o C= 0.56 (72-32) = 22.2 o C </li></ul><ul><li>K= o C +273.15 = 22.2 =273.15=295.4K </li></ul>
  • 31. Conversion Example 3 <ul><li>Since both K and R start at 0: </li></ul><ul><li>K = 5/9 R and R = 9/5 K </li></ul><ul><li>So the last problem could have went: </li></ul><ul><li>72 o F + 460= 532 R </li></ul><ul><li>532R * .56 = 295.6K </li></ul><ul><li>(Rounding error – we’ll cover that later) </li></ul>
  • 32. Dimensional Analysis <ul><li>If you think it’s hard, we just did it on the past two slides. </li></ul><ul><li>It is a great way to check an answer </li></ul><ul><ul><li>If you know you are looking for a density in kg / m 3 , the units in your calculation need to cancel to kg / m 3 . </li></ul></ul>
  • 33. Dimensionless Numbers <ul><li>Dimensionless numbers are used extensively in engineering </li></ul><ul><li>The are ratios of two derived units that relate to the concept at hand (like the ratio of dynamic pressure to shearing stress: the Renyolds number N Re ) </li></ul><ul><li>For systems with N Re < 2,500 there is laminar flow, over 4,000 is turbulent flow, and in between is a transition area. </li></ul>
  • 34. Significant Figures <ul><li>Accuracy vs Precision: </li></ul><ul><ul><li>Accuracy is shooting the apple off of someone's head three times </li></ul></ul><ul><ul><ul><li>Once hitting the top of the apple </li></ul></ul></ul><ul><ul><ul><li>Once hitting the left side </li></ul></ul></ul><ul><ul><ul><li>Once hitting the bottom and slicing your friends scalp </li></ul></ul></ul><ul><ul><li>Precision is missing the apple all three times, but putting all the arrows between your friends eyes </li></ul></ul><ul><ul><li>Accuracy & Precision is knocking the thing off by hitting the center all three timesm </li></ul></ul>
  • 35. Significant Figures <ul><li>When we take a measurement, we can see the gap between two marks and estimate the fraction between those marks </li></ul><ul><ul><ul><ul><ul><li>4.75 </li></ul></ul></ul></ul></ul>1 4 5 6 2 3
  • 36. Significant Figures <ul><li>Your answers need to reflect how accurate they are </li></ul><ul><li>Even if your calculator can display 16 digits, unless your working for NASA or Lockheed, you don’t need all of them </li></ul><ul><li>Add or Subtract – count decimals </li></ul><ul><li>Multiply or Divide – count Sig Figs </li></ul>
  • 37. Significant Figures <ul><li>For ADDING or SUBTRACTING : </li></ul><ul><ul><li>The number of digits in the number LEAST decimal places is the number of Sig Figs </li></ul></ul><ul><ul><ul><li>547.9 4 Sig Figs </li></ul></ul></ul><ul><ul><ul><li>1.003 4 Sig Figs </li></ul></ul></ul><ul><ul><ul><li>10,325. 5 Sig Figs </li></ul></ul></ul><ul><ul><ul><li>10,325 4 Sig Figs (no decimal point means the last digit is the estimated one) </li></ul></ul></ul>
  • 38. Significant Figures <ul><li>Addition: </li></ul><ul><li>85.321 </li></ul><ul><li>+ 67.235 </li></ul><ul><li>139.47 </li></ul><ul><li>292.026 </li></ul><ul><li>139.47 has the least decimal places and thus is the least precise, so your answer can only be that precise. The answer must be rounded to 292.03 </li></ul>
  • 39. Significant Figures <ul><li>Multiplication & Division : </li></ul><ul><ul><li>The number of Sig Figs is equal to the number with the least Sig Figs. </li></ul></ul><ul><ul><li>Let’s say you measure a rectangle and your measurements are 32.5123 and 10.25 – your least precise number has 4 Sig Figs, so your answer can not have more that that. </li></ul></ul>
  • 40. Significant Figures <ul><li>What is the volume of cylinder where you measured the height as 8.5 cm and the diameter 2.25 cm? </li></ul><ul><li>V=1/4∏d 2 * h </li></ul><ul><li>V= 0.25 * 3.14159 * (2.25) 2 * 8.5 </li></ul><ul><li>V= 33.7967 – the number of Sig Figs is 2 (8.5) so the number is rounded to 34 . </li></ul>
  • 41. Questions?

×