1. What is Science Study of the physical universe An organized body of facts Experimentation –Observation Cannot be vague Avoid inference

2. Scientific Method – is a problem solving process Define the problem – ask a question Form a hypothesis – educated guess Test the hypothesis – use the tools of science Accept or reject hypothesis – evaluate data Reformulate hypothesis Verify hypothesis - retest

3. Measurement in Science Scientific Notation – a shorthand method for writing very large and small numbers Metric System – an international measurement system that uses the decimal system units of division (base 10) Significant Figures – any measurement which is reliable

4. Scientific Notation Numbers are expressed as a value between 1 and 10 (not 10) times 10 raised to a power –Ex. 2.15 x 10 -7 = 0.000000215 ● Addition and Subtraction – exponents must have the same value ● Multiplication – add exponents ● Division – subtract exponents

5. Addition and Subtraction 7.55 x 10 -7 +2.45 x 10 -5 Must change exponents to match 7.55 x 10 -7 + 245. x 10 -7Note: the exponent got 252.55 x 10 -7 smaller so the number gets bigger Final correct ans. 2.5255 x 10 -5 Subtraction follows the same rule

6. Multiplication – add exponents 5.39 x 10 5 x 3.21 x 10 3 17.30 x 10 8 Note: the answer is not in proper scientific notation 1.73 x 10 9 Proper Scientific Notation

7. Division – subtract exponents 7.26 x 10 5 ÷ 3.21 x 10 3 = 226 Note: the answer is not in proper scientific notation 2.26 x 10 2 Proper Scientific Notation 2.08 x 10 -6 = 0.648 x 10 -1 3.21 x 10 -5 Note: the answer is not in proper scientific notation 6.48 x 10 -2 Proper Scientific Notation

8. Metric System Basic Units –Meter – length –Gram – mass –Cubic decimeter (or Liter) – volume –Kelvin (or Celsius) – temperature –Seconds – time –Joules – energy

9. Metric System Prefixes kilo - 10 3 - 1000 times basic unit hecto - 10 2 - 100 times basic unit deka – 10 1 – 10 times basic unit deci - 10 -1 - 0.1 times basic unit centi -10 -2 - 0.01 times basic unit milli - 10 -3 - 0.001 times basic unit micro - 10 -6 - 0.000001 times basic unit Metric converter - is helpful when learning conversions

10. Metric Converter SmallerPrefixFactorScientific Notation units nano (n)1/1,000,000,000   micro (   milli (m)1/1000   centi (c)1/100   deci (d)1/10   Standard(Meter, Liter, 1   unitGram) deka (D)10   hecto (h)100   kilo (k)1000   mega (M)1,000,000   giga (G)1,000,000,000   Larger Units Decimal Point Movement

11. Significant Figures (digits) Accuracy – difference between a measured value and the true or accepted value Precision – degree of agreement between measured values

12. Accuracy vs. Precision AccuratePreciseAccurate and Precise Note: The accurate target is not precise but the average of the values is accurate

13. Significant Figures Rules for defining significant figures - Leading zeros are not significant Ex: 0.000025 -Trailing zeros are not significant unless there is a decimal point following them Ex: 2500000

14. Significant Figures (cont.) -Captive zeros are always significant Ex: 2003, 70.005, 0.0090006 -Zeros to the right of a decimal and a non-zero number are always significant Ex: 0.3500,0.0000770, 90.000

15. Significant Figures Rules of Operations –Addition and subtraction – the limiting term is the one with the smallest number of places to the right 6.3451.00945 +0.125045 - 0.210 6.4700.799

16. Significant Figures Rules of Operation (cont.) –Multiplication and division – the answer contains the same number of significant figures as the value with the smallest number of significant figures 9.1100.4521 = 0.374 x 0.025 1.21 0.23 Ans: 2 sig. figs. Ans: 3 sig. figs