Note Taking in my class

Transcription

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2 Note Taking in my class! If it is underlined you need to know it for the test.! I do not do notebook checks.! You are responsible for taking and keeping up with your notes.! Note material will be seen in lab, on quizzes, and on tests.! Always bring your notes to class in case you are allowed to use them on a pop quiz.! If you don t have them, tough.

3 I. Branches of Science! Natural science is generally divided into three main branches! a)physical Science : nonliving this class! b) Earth and space junior & senior years for most of you! c) Life Science: living(biology)---next year for most of you

4 The Big Ideas of Physical Science! 1. Space and Time! 2. Matter and Change

5 3. Forces and motion! Forces cause change in motion! 4. Energy! a. exists in many forms! b. can be transferred, but never created or destroyed

6 II. The Scientific Method!The goal is to solve a problem or better understand an observed event.

7 The Scientific Method Steps 1. Observe 2. State a question 3. Hypothesis proposed answer to the question 4. Experiment- test your hypothesis 5. Collect data 6. Draw a conclusion 7. Theory(prediction)-explanation of well observed events.

8 The Experiment! 1. Manipulated (independent) variable causes change in another (changed deliberately)! 2. Responding (dependent) variable- changes in response to the manipulated variable (observed for changes)! 3. Controlled(constant) variable- things that you need to consider but are not testing

9 If and Then! A good way to identify the manipulated and responding variable is by making an if and then hypothesis.! For example: If I eat carrots, then I will have 20/20 vision.! Eating carrots is the manipulated variable.! Perfect vision is the responding variable.

10 Think about it!what are the variables in this example?:!if I take notes in class, then I will make good grades.

11 Scientific Law! Statement that summarizes a pattern in nature without attempting to explain it. The explanation of such a pattern is provided by a Scientific Theory.! Scientific Models A representation of an object or event.! Make it easier to understand things that might be too difficult to observe directly

12 III. Representing Scientific Data! Types of graphs! 1. Line Graph- useful for showing changes that occur over a period of time

13 2. Bar Graph! Bar graphs are used to compare a set of measurements

14 3. Circle Graph! Also know as a pie chart shows parts of a whole

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16 Base Units!Length = meter!mass (amount of matter in an object)= gram!volume (space taken up by an object)= Liter!Temperature = Kelvin (but we usually use Celsius in the lab)

17 Abbreviations! Meter = m (lowercase m)! Gram = g (lowercase g)! Liter = L (capital L)! Kelvin = K (capital K)! Celsius = C (capital C)

18 Prefixes! Giga- = G = 10 9! Mega- = M = 10 6! Kilo- = k = 10 3! Hecto- = h = 10 2! Deka- = da = 10 1! Base unit (gram, liter, meter)! Deci- = d = 10-1! Centi- = c = 10-2! Milli- = m = 10-3! Micro- = μ = 10-6! Nano- = n = 10-9

19 Most used prefixes the ones you will have to memorize!!! Kilo- = k = 10 3! Hecto- = h = 10 2! Deka- = da = 10 1! Base unit (gram, liter, meter)= 10 0! Deci- = d = 10-1! Centi- = c = 10-2! Milli- = m = 10-3! King Henry Died by Drinking Chocolate Milk

20 Cheat Chart *! km hm dam m dm cm mm! kg hg dag g dg cg mg! kl hl dal L dl cl ml! * You are not allowed to use this on your test!

21 Convert the following! 550mm m! 3.5g mg! 1.6kg g! 2500mg kg! 4.00cm mm! 2800mL L! 6.1g mg! 3L cl! 0.55m! 3500mg! 1600g! kg! 40.0mm! 2.8L! 6100.mg! 300cL

22 Convert the following! 12.2 kg = g! 3.5 cm = mm! 750m = km! 8 x 10 8 cm = km! g! 35 mm! km! 8 x 10 3 km

23 Examples! A tablespoon of butter has a mass of about 1 gram.! One kilogram has a weight of 2.2 pounds.

24 Examples! A meter is about the distance from you fingertip to your nose.! A centimeter is about the width of the end of your pinky finger.! A millimeter is about the width of the tip of your pencil or pen.! A kilometer is just a little less than a mile

25 Examples! 1 liter is about 4 cups (the measuring kind) or just over 1 quart (like a quart size jar).! 1 gallon is just under 4 liters.! 1 kiloliter is about 264 gallons (like gallon cartons of milk).! 1 milliliter is about the same as a water droplet.

26 V. Measurement! Scientific Notation- way of expressing a value as the product of a number between 1 and 10 and a power of ten.! 1. It makes a very large or very small number easier to work with.! Ex. 6,000,000,000 =6.0 x 10 9! Ex = 8.6 x 10-5

27 Scientific Notation Rules!There must be only 1 number in front of the decimal.!the number cannot be 0.!The proper format is a single number x 10 to an exponent.

28 Scientific Notation Rules Continued!Numbers greater than 1 have a + exponent.!numbers less than 1(decimal numbers) have a exponent.

29 Scientific Notation Rules Continued!The exponent s number comes for the number of places you moved the decimal to get a single digit (non zero) number.

30 Put the following Scientific Notation! a. 4000! b ! 4.0 x 10 3! 5.6 x 10-2! c. 200,000,000,000! 2.0 x 10 11! d ! e ! 1.5 x 10-5! 5.6 x 10 2

31 Report the following numbers in scientific notation!784! ! !5,000,000,000!37,000.! !7.84 x 10 2!7.8 x 10-4!3.03 x 10-8!5 x 10 9! x 10 4! x 10-2

32 Take the following numbers out of scientific notation!2.3 x 10 5!6.512 x 10-3!9.00 x 10-2!3.033 x 10 8! x 10 2! x 10-7!230,000! ! !303,300,000! !

33 Practice Problems! 1.5 x 10 5! 2.6 x 10 2! 3.5 x 10 4! 1.8 x 10-6! 5.1 x 10-3! 165.3! 26.2! ! 0.258! ! 260! ! ! ! x 10 2! 2.62 x 10 1! 1.5 x 10 5! 2.5 x10-1

34 Adding and subtracting exponents Multiplying Scientific Notation! Add exponents! 10 3 x 10 6 =! 10 4 x 10-7 =! 10-5 x 10-6 =! 10-9 x = Dividing Scientific Notation! Subtract exponents! 10 6 / 10 5 =! 10-5 / 10-6 =! 10 3 / 10-3 =! 10-2 /10-2 =

35 Area (A=l x w) Work the following! A rectangular parking lot has a length of 1.1 x 10 3 meters and a width of 2.4 x 10 3 meters. What is the area of the parking lot?! (1.1 x 10 3 ) x (2.4 x 10 3 )! (1.1 x 2.4) = 2.64! ( ) = 10 6! A= 2.6 x 10 6 m 2! Length = 1.1 x 10 3! Width = 2.4 x 10 3

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37 Limits of measurements Significant Figures! The more significant figures the more precise measurement you get. Precise vs. Accurate! Accurate is getting the expected (correct) result.! Precise is getting the same result repeatedly.! The goal should be to be accurate and precise.

38 Significant Digits! Each recorded measurement has a certain number of significant digits.! Any digit that is actually measured or estimated is significant.! Placeholders are not significant.! We mainly use this in the lab.

39 Significant Digits Rules 1.Digits from 1-9 are always significant.

40 Significant Digits Rules 2. Zeros between two other significant digits are always significant. (203)

41 Significant Digits Rules 3. One or more additional zeros to the right of both the decimal place and another significant digit are significant. ( but not 2000)

42 Significant Digits Rules 4. Zeros used solely for spacing the decimal point are not significant. (0.2)

43 Report how many significant digits are in each number! 345.1! ! ! ! ! 2,000,000,000! 500,000.! 4! 3! 6! 3! 5! 1! 6

44 When you multiply or divide..!your answer can only have as many significant digits as the part of the problem that has the LEAST significant digits.

45 When you add or subtract!your answer can only show as many decimal places as the measurement that has the fewest DECIMAL places.

46 Do the following calculations and report your answer in the correct # of significant digits!820 x =! =! /2.4 =!8,000,200 x =!267, =!28,000!8.926!0.035!8.000 x 10 7!268,300!25,600!8740/ =

47 VII. Temperature!There are 3 temperature scales:!kelvin = K!Fahrenheit = 0 F!Celsius = 0 C

48 Absolute Zero! 0 K is absolute zero.! It is the temperature at which all atoms completely stop moving.! 0 K = -273 O C = O F! Kelvin is the only scale that can t have a negative reading.

49 To convert from O F to O C! O C=5/9 ( O F-32.0)! First plug in for O F.! Then do what is in parenthesis.! Then say 5 9 x the number you got in parenthesis.

50 To convert from O C to O F! O F=9/5( O C) +32.0! First plug in for O C.! Then say 9 5 x the number you plugged in.! Then add 32 to that answer.

51 To convert from O C to K! K = O C + 273! Plug in for O C and add.! To find O C from K:! O C = K -273! Plug in for K and subtract.

52 The hard part.! There is not an easy formula to convert from Fahrenheit to Kelvin or vice versa.! It is a 2 step process.! First you have to convert to Celsius and then from Celsius to what you are actually trying to find.

53 Practice.! O C=5/9 ( O F-32.0)! O F=9/5( O C) +32.0! K = O C + 273! 25 O C = O F! 112 O F= O C! 400K= O C! 22 O C= K! 65 O F= K! 280K= O F

54 VIII. Density! Density = mass/volume! Think of density as relative heavy-ness.! If an object s density is greater than the liquid it is in, it will sink.! What would make an object float?! Which is more dense:! A rock or a crumpled ball of paper?! Oil or water?

55 Density Practice! D=m/v! 1mL = 1cm 3! Find D if m=63.5g and v=20.3ml.! Find m if D=900g/cm 3 and v=65cm 3.! Find v is D=63g/mL and m=500g.

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