Unit 1: Introduction to Chemistry

1. Unit 1: Introduction to Chemistry This alchemist is searching for the Philosopher’s Stone. He should’ve just asked Dumbledore. This modern chemist was playing Solitaire but quickly Alt-Tabbed out as the picture was snapped.

2. Safety • There are two things wrong with this picture. What are they? • 1) There is an uncontrolled flame. • 2) Where are Beaker’s goggles?

3. Safety II • Since we do not want to pull a Beaker, let us visit our Safety Rules for the classroom. • Follow these, or else. • “Or else what?” You ask…are you sure you want to know?

4. Or else you’ll be like this… • http://www.youtube.com/watch?v=V-fNpaOX0-g • I don’t want you to be like that. • You don’t want to be like that. • So let’s just avoid that altogether, okay?

5. Course Syllabus • Here it is

6. Unit 1 Objectives • It is important to work safely and efficiently in the laboratory. • Quantitative data is best organized in tabular or graphical form. • The scientific method is used in problem solving. • Chemistry is a physical science which deals with the structure of matter. • The states of matter are distinguished by their molecular structure. • Matter and energy are related. • Physical and chemical properties are useful to the chemist. • The Laws of Conservation explain many chemical concepts. • Significant figures are used to analyze the accuracy of measurements. • The magnitude of a number is best illustrated with scientific notation. • Dimensional analysis is a logical approach to problem solving. • Density is an intensive physical property. • Heat and temperature are related. • The SI system is the “scientific” system of measurement.

7. Essential Questions • How do scientists obtain and record consistent data? • Could the scientific method be used to solve any problem? • What are the distinctions between matter and energy? • Guiding Questions: • What are safe laboratory procedures? • What is the role of observation in science? • How is chemistry defined? • Why are chemical and physical properties important? • What is correct scientific notation? • When is a number significant, but not important and when is it important, but not significant? • How are significant figures used in calculations? • What is the difference between accuracy and precision and how are they measured? • How is quantitative data analyzed? • How does the SI system of measurement compare to the English system of measurement? • Why is dimensional analysis used in problem solving? • Why is density important? • How are heat and temperature related? • Where did the energy go? • Define what a system is and determine if things are or are not systems.

8. Your Take • What would you like to add? • Covalent Bonds P1 • Why are modern electronics so expensive? P1 • How blimps fly? P1 • What are “rings” around an atom in pictures for? P1 • How do fireworks come in different colors? P1 • How does an atom split in nuclear bombs? P1 • How are new elements discovered? P4 • How do you make gunpowder? P4 • How does nuclear energy work? P4 • What makes something radioactive? P4 • Why is there radioactive potassium in bananas? P4 • Why are aerosol cans flammable? P4 • Why is powdered milk flammable? P4 • How are plastics made? P6 • What elements can stars fuse? P6 • Do black holes and chemistry have anything in common? P6 • Where do element abbreviations come from? P6 • How do you make glass? P6 • Why does gatorade contain flammable materials? P6 • How does technology detect individual elements? P7 • Why do scientists not turn less useful elements into useful elements? P7 • Why are they called “noble” gases? P7 • How many elements are in the human body? P7 • How are new colors created? P7

9. Castagno Chemistry Challenge • Rules: • 1) Other than those able to respond, keep quiet or risk class disqualification • 2) Each student must answer 1x first • 3) Each desk then responds in order • 4) Challenge ends when a student or desk cannot respond. • 1st – 2pts, 2nd – 1pt, 3rd – 0pts, 4th – 0pts • Questions?

10. The Challenge • Name as many elements as possible.

11. What Is Chemistry? • Biological science studies life • Physical science studies non-life • Chemistry bridges the gap

12. Minded the Gap • How does sugar bridge the gap? • Sugar is not a living substance. • However, when utilized, provides the energy for us to live.

13. Matter What is mind? No matter. What is matter? Nevermind! • It is VERY important, Homer. • This is what chemists study. • But what IS it? • For us, matter is “anything that has mass and takes up space.” • So what is everything else?

14. Everything Else • Energy! • Let’s just say “light and heat” • Neither have mass • Neither have volume • But what if something is neither matter nor energy?

15. That Empty Feeling • For all intents and purposes: nothing. • Though to Laurence Krauss nothing = everything! • For us, though, we will see how most of our being (and therefore everything) is empty.

16. Time to study, but where? • In your groups, determine what type of chemist would study the following: • 1) DNA • 2) “blueberries” • 3) cis-2-butene • 4) Zeolites • 5) C13 NMR • 6) Phase change • 7) Room-temperature Superconductors • 8) Contaminants

17. Branches of the Chemistree Biochemistry Analytical Physical Inorganic Theoretical Environmental Organic Astrochemistry Move On

18. Organic • The largest branch of chemistry • Study carbon containing compounds • Right of passage for collegiate chemistry Back

19. Inorganic • Not the opposite of organic • Carbon can be, and often is, present • Grubb’s Catalyst (2005 Nobel Prize Winner) contains 43 carbon atoms out of 120 atoms (35.8%) • Also include silicones among many others Back

20. Analytical • Identification and quantification of substances • Range from high to low tech techniques Back

21. Biochemistry • Studies substances in biological systems • Clearly overlaps organic chemistry as we are all CARBON-based lifeforms Back

22. Physical • Looks at chemical behavior from a physics point of view • Thermochemistry (heat and energy) • Intermolecular forces Back

23. Theoretical • Like any theoretical branch of science, it is attempting to explain observed phenomena. Back

24. Environmental • Study of how chemicals and biological materials react naturally • “Green Chemistry” is an attempt to reduce pollution at the source. Back

25. Astrochemistry • Study of chemistry…just in space. Back

26. Discovery • Sometimes happens by chance • I’m looking at YOU, Columbus! • Benzodiazepine (therapeutic drugs, Valium) were forgotten for over a year and then almost THROWN AWAY before a sample was retested. • Made Hoffman-La Roche MILLIONS of dollars • But typically the result of a well developed process

27. The Scientific Method • The logical problem solving approach • But what is the order? • If you do not remember the exact word, you can describe the step.

28. Observation • The most important tool in any scientist’s arsenal. • Obtain qualitative (descriptive) and quantitative (numerical) data.

29. Hypothesize • It is impossible to develop an experiment without having something to test. • The testable statement is the hypothesis • Generalization of your observed data

30. Testing (Experimentation) • An attempt to validate the hypothesis • Conditions may be constant (control) • Or changing (variable)

31. Analysis of Data • ALL data is important • It can relate directly to your experiment • It can lead you down a new path of discovery • Properly organized using tables, charts, graphs, calculations.

32. Conclusion • This is when you attempt to explain results • Model: an explanation to how the observed phenomena occurs (Atomic Model) • Theory: a broad generalization that explains a body of facts (Evolution)

33. Measurements • In the course of obtaining data, often times different tools are used and different numbers are recorded. • This is expected and not a sign of making mistakes. • However, for clarity and consistency, we may need to make adjustments.

34. Taking Measurements • Have you ever heard that “a human’s wingspan is equal to their height?” • Can be seen in Da Vinci’s “Vitruvian Man”

35. Let’s Test It • At each table, measure the wingspan and height in using meters (cm and mm too) • Find the ratio – height / wingspan • Place your results on the board. • Is Da Vinci correct?

36. Scientific Notation • When numbers obtained are REALLY big or REALLY small, there are a lot of digits: • The Spaces added within the number are for clarification • Avogadro’s Number (amount) • 602 214 179 000 000 000 000 000 • Mass of the electron (kg) • 0.000 000 000 000 000 000 000 000 000 000 9109

37. Scientific Notation II • The purpose of scientific notation is to shorten the number by eliminating as many zeros as possible. • Avogadro’s Number (amount) • 6.02214179 x 1023 • Mass of the electron (kg) • 9.109 x 10-31

38. Scientific Notation III • Before some example demonstrations • Note the following • 1) Values greater than 1 have a positive exponent • 2) Decimal values (between 1 and 0) have a negative exponent • 3) The value of the exponent represents the number of places the decimal moved

39. Significant Figures • Add the following • 2.105 • 103.3 • 42.94 • 1.3013 • What do you get?

40. Significant Figures II • Did you get 149.6463? • Is that correct? • Are you sure? • Did your calculator tell you? • Remember your calculator is only going to do what you TELL it to, not what you WANT it to do. • Are you still sure?

41. Significant Figures III • What about now 1.3013 2.105 42.94 103.3 • Notice anything? • Still think it is 149.6463?

42. Significant Figures IV • Here is the big problem 1.3013 2.105 42.94 103.3 149.6463 • Do you know what these #s are?

43. Significant Figures V • We CANNOT say those ?s are 0. • There is a 1 in 10 chance each ? is a 0 • which means (1/10)^6 or a • 1 in a MILLION chance the answer is 149.6463! 1.3013 2.105 42.94 103.3 149.6463 • So what IS the answer?

44. Significant Figures VI • We can only say for sure each number to their 1st decimal (tenths) place. • Therefore, our answer must reflect that 1.3013 2.105 42.94 103.3 149.6463 • So the answer is – 149.6

45. Accuracy and Precision • Accuracy • “closeness of a measurement to an accepted value” • In other words, how close to the target or goal are you? • Precision • “closeness of a set a measurements” • We’re going to need an example

46. Our Target • In order to compare the accuracy of the upcoming event, we need to base the determination on Calvin’s location. • To gauge the precision, we need to look at the location of the various projectiles.

47. “Measurement” • What can I say? Science is messy sometimes.

48. Accurate or Precise? • Accuracy: Certainly so as Calvin got hit numerous times. • Precise: the snowballs are in a close location to other snowballs.

49. Accuracy and Precision II • Both A & P – close to goal and self • A, not P – ‘close’ to goal, not self • P, not A – close to self, not goal • Neither A nor P – Not close to self nor goal • How accurate, precise, or neither are you?

50. SI System • Our Standard system of measurement includes numerous oddities: • 1 gal = 4 qt = 16 cups = 256 tbsp = 768 tsp • The SI System, once mastered, is much easier to use if you know how to move a decimal!