3.  It is the steps someone takes to identify a question, develop a hypothesis, design and carry out steps or procedures to test the hypothesis, and document observations and findings to share with someone else.

5. The question leads one to… gather information (you find s Thomson’s Plum Pudding Model for atomic structure- there are electrons embedded in a sea of positive charge) and form a hypothesis ( If Thomson's Plum Pudding model was to be accurate, then big alpha particles will pass through the gold foil with only a few minor deflections because alpha particles are heavy and the charge in the "plum pudding model" is widely spread.)

7.  Finally you gather information based on your experiment, analyze the data to determine what your experiment showed you about the phenomena you questioned, and come up with a conclusion based on it. Was your hypothesis correct? Incorrect? Why? What other questions does it leave you with?

8.  Observations lead to Questions  Background Research-what do we already know  Hypothesis- what do we expect will occur  Conduct Experiment- Procedures/Method  Collect and Analyze Results/Table/stats/graphs  Conclusion

9.  IS SCIENCE OBJECTIVE OR SUBJECTIVE???

13.  …ON HOW CLOSE WE LOOK… CONCLUSIONS ARE NEVER OBJECTIVE…ALWAYS SUBJECTIVE

14.  Scientific theory- explanation that has been tested by repeated experiments Theories must explain observations simply and clearly (theory that heat is the energy of particles in motion explains how the far end of a metal tube gets hot when placed in an open flame) Experiments must illustrate theory is repeatable ( the far end of the tube ALWAYS gets hot regardless of how many times it is done) You must be able to make predictions based on it. ( you might predict that anything that makes particles move faster will make the object hotter. Sawing a piece of wood will make the particles move faster, and will make it hotter as well.) Scientific law states a repeated observation of nature but doesn’t explain why warm objects become cooler.

15.  Equations describes relationships between quantitative measurements  It is a universal language. Universal law of gravitation

16.  Represent things that are either too large, small, or complex to study easily. Also to as a mental picture to predict what will happen (eg. Chemical equations)  Computer models-often mathematical models that can save time and $$ because calculations are done by machines (eg. Crash test for motion/forces to improve car design)

17.  WHY SI??? To be on the same page…comparing apples to apples (meters to meters, liters to liters)…KING HENRY!

19.  SI prefixes are for very large or very small measurements…instead of expressing that you traveled 800,000 m in distance, you would use 800 km to avoid using several zeros.  SI prefixes are in multiples of 10.  This makes it easy to convert SI units into larger or smaller units by moving the decimal.

20.  If a person’s height is 1.85 m, how many cm is this person?  1.85 m x 100 cm = 185 cm ------------- m DOES THIS MAKE SENSE???

21. Using the Metric System Scientific Notation Percent Error Using Significant Figures Accuracy and Precision Graphing Techniques

22. QUANTITY NAME SYMBOL _______________________________________________ Length meter m ----------------------------------------------------------------------------- Mass kilogram kg ------------------------------------------------------------------------------- Time second s -------------------------------------------------------------------- Amount of Substance mole mol

23.  Base Units – independent of other units  Derived Units – combination of base units Examples  density  g/L (grams per liter)  volume  m x m x m = meters cubed

24.  Make conversions by moving the decimal point to the left or the right using: “ k ing h enry d ied unit d rinking c hocolate m ilk” Examples 1. 12.0 cm = __________m 2. 39.5 mL = __________L 3. 28.7 mg = __________kg

25.  Scientific Notation: Easy way to express very large or small numbers  A.0 x 10 x  A – number with one non-zero digit before decimal  x -exponent- whole number that expresses the number decimal places  if x is (-) then it is a smaller  if x is (+) than it is larger

26.  Convert to NormalConvert to SN  2.3 x 10 23 m3,400,000, 3.4 x 10 -5 cm.0000000456

27.  Calculating in Scientific notation  Multiplying-  Multiple the numbers  Add the exponents  (2.0 x 10 4 ) (4.0 x 10 3 ) = 8.0 x 10 7

28.  divide the numbers  subtract the denominator exponent from the numerator exponent  9.0 x 10 7 3.0 x 10 2  3.0 x 10 5

29.  Add or subtract  get the exponents of all # to be the same  calculate as stated  make sure the final answer is in correct scientific notation form  7.0 x 10 4 + 3.0 x 10 3 =  7. 0 x 10 4 +.3 x 10 4 = 7.3 x 10 4  70,000 + 3,000 = 73000= 7.3 x10 4

30.  7.0 x 10 4 - 3.0 x 10 3 =  7.0x 10 4 –.30 x 10 4 = 6.7 x 10 4  70,000 - 3 000 =67,000

31. Add: 2.3 x 10 3 cm + 3.4 x 10 5 cm Subtract: 2.3 x 10 3 cm - 3.4 x 10 5 cm Multiply: : 2.3 x 10 3 cm X 3.4 x 10 5 cm Divide: : 2.3 x 10 3 cm / 3.4 x 10 5 cm

32.  The absolute value of the difference between the value obtained (what you measured) and an ideal value (what you should have obtained)  Divided by the ideal value (what you should’ve obtained)  Times 100.

33. % Error =accepted value–experimental value X 100= % accepted value Subtract -Divide then multiply by 100

34. EXAMPLE – A student determines the density of a piece of wood to be.45g/cm. The actual value is.55g/cm. What is the student’s percent error?.55 -.45 X 100% =.10 =.18 x 100% = 18%.55.55

35.  If someone asks you how many inches there are in 3 feet, you would quickly tell them that there are 36 inches.  Simple calculations, such as these, we are able to do with little effort.  However, if we work with unfamiliar units, such as converting grams into pounds, we might multiply when we should have divided.

36. The fraction ( 4 x 5) / 5 can be simplified by dividing the numerator (top of fraction) and the denominator (bottom of fraction) by 5: Likewise, the units in (ft x lb) / ft reduces to pounds (lb) when the same units ( ft )are canceled: = 4 = lb

37.  A CONVERSION FACTOR is a given Ratio- Relationship between two values that can also be written as TWO DIFFERENT FRACTIONS.  For example, 454 grams =1.00 pound, states that there are 454 grams in 1.00 pound or that 1.00 pound is equal to 454 grams.

38.  We can write this Ratio-Relationship as two different CONVERSION-FACTOR- FRACTIONS :  These fractions may also be written in words as 454 grams per 1.00 pound or as 1.00 pound per 454 grams, respectively. The "per" means to divide by. or as

39. If we want to convert 2.00 pounds into grams, we would:  first write down the given quantity (2.00 lbs)  pick a CONVERSION-FACTOR-FRACTION that when the given quantities and fractions are multiplied, the units of pounds on each will cancel out and leave only the desired units, grams. We will write the final set-up for the problem as follows: = 908 grams

40. If we had used the other conversion-factor- fraction in the problem: We would know that the ABOVE problem was set-up incorrectly since WE COULD NOT CANCEL Out the units of pounds and the answer with pounds / grams makes no sense. =

41. When using the Factor-Label Method it is helpful to follow a four-step approach in solving problems : 1. What is question – How many sec in 56 min 2. What are the equalities- 1 min = 60 sec 3. Set up problem (bridges) 56 min 60 sec 4. 1 min 5. Solve the math problem -multiple everything on top 6. and bottom then divide 56 x 60 / 1

42.  value determined by the instrument of measurement plus one estimated digit  reflects the precision of an instrument  example – if an instrument gives a length value to the tenth place – you would estimate the value to the hundredths place

43. 1. all non-zero # are Sig fig- 314g 3sf 12,452 ml 5sf 2. all # between non-zero # are sig fig 101m 3sf 6.01mol 3sf 36.000401s 8s 3. place holders are not sf0.01kg 1sf

44. 4. zeros to the right of a decimal are sig fig if 3.0000s 5sf Preceded by non-zero 0.002m 1sf 13.0400m 6sf 5. Zero to right of non-zero w/o decimal point600m1sf are not sig fig600.m3sf 600.0 m 4sf 600.00 m 5sf

45.  use the arrow rule to determine the number of significant digits  decimal present all numbers to right of the first non zero are significant (draw the arrow from left to right) ----------> 463 3 sig. digits ----------> 125.78 5 sig. digits ---------->.0000568 3 sig. digits ----------> 865 000 000. 9 sig. digits

46.  use the arrow rule to determine the number of significant digits  decimal not present < -------- all numbers to the left of the first non zero are significant (draw arrow from right to left) 246 000 <---------- 3 sig. digits 400 000 000 <---------- 1 sig. digit

47.  If the last digit before rounding is less than 5 it does not change ex. 343.3 to 3 places  343 1.544 to 2 places  1.54  If the last digit before rounding is greater than 5 – round up one ex. 205.8 to 3 places  206 10.75 to 2 places  11

48. 1) 2) 3) 4) 24.05 5.6 237.52 88 123.770 28 - 21.4 - 4.76 0.46 8.75 10.2 7 _________ ______ _______ ______

49. 1) 23.7 x 6.36 2).00250 x 14 3) 750. / 25 4) 15.5 /.005

50.  ACCURACY – how close a measured value is to the accepted value  PRECISION – how close measurements are to one another - if measurements are precise they show little variation * Precise measurements may not be accurate

51. Precision- refers to how close a series of measurements are to one another; precise measurements show little variation over a series of trials but may not be accurate. LESS THAN.1 IS PRECISE Oscar performs an experiment to determine the density of an unknown sample of metal. He performs the experiment three times: 19.30g/ml 19.31g/ml 19.30g/ml Certainty is +/-.01 Are his results precise?

52.  Accuracy – refers to how close a measured value is to an (theoretical) accepted value.  The metal sample was gold( which has a density of 19.32g/ml)  Certainty is +/-.01  Are his results accurate? Need to calculate percent error.  5% OR LESS IS ACCURATE  Oscar finds the volume of a box 2.00cm3 (ml)  It is really 3.00ml is it precise? Accurate? Percent error

53.  Oscar finds the volume of a box 2.00cm 3 (ml)  It is really 3.00ml is it precise? To know if it is precise you need more trials  Accurate? Percent error Actual - Experimental X 100% = Actual 3-2 3 X 100 = 33.3%

54.  Activity: basket and paper clip  1. Throw 6 paper clips at basket  2. Measure the distance from the basket to determine accuracy and precision  Cm 3 = ml and dm 3 = l Liter PAPER CLIP LAB:  Q- Will I be able to precisely and accurately throw 6 paper clips in a basket located ____________ cm away?  H:

55.  graph – a visual representation of data that reveals a pattern  Bar- comparison of different items that vary by one factor  Circle – depicts parts of a whole  Line graph- depicts the intersection of data for 2 variables  Independent variable- factor you change  Dependent variable – the factor that is changed when independent variable changes

56.  Creating a graph- must have the following points 1. Title graph 2. Independent variable – on the X axis – horizontal- abscissa 3. Dependent variable – on Y axis – vertical- ordinate 4. Must label the axis and use units 5. Plot points 6. Scale – use the whole graph 7. Draw a best fit line- do not necessarily connect the dots and it could be a curved line.

57.  Interpreting a graph  Slope- rise Y2 –Y1  Run X2 –X1  relationship  direct – a positive slope  inverse- a negative slope  equation for a line – y = mx + b  m-slope  b – y intercept  extrapolate-points outside the measured values- dotted line  interpolate- points not plotted within the measured values-dotted line

58.  Creating a graph- must have the following points 1.Title graph 2. Independent variable –on the X axis–horizontal- abscissa 3. Dependent variable – on Y axis – vertical- ordinate 4. Must label the axis and use units 5. Plot points 6. Scale – use the whole graph 7. Draw a best fit line- do not necessarily connect the dots and it could be a curved line.

59.  Interpreting a graph  Slope= rise Y2 –Y1  Run X2 –X1  relationship  direct relationship– a positive slope  Inverse relationship- a negative slope  equation for a line – y = mx + b  m-slope  b – y intercept  extrapolate-points outside the measured values- dotted line  interpolate- points not plotted within the measured values-dotted line

60.  PROPERTIES AND CHANGES  CLASSIFICATION OF MATTER