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What are the steps in the Scientific Method?
 Observation: .
 Hypothesis: Working model
 Test: Hypothesis has to be consistent with observations
 Theory: Based on common principles, reason, logic, math
 Test/Experimenting: .
 Laws: Developed from theories. Until someone else makes a different observation

What are the two different types of Observations?
 Qualitative: What color is it? Smell? Liquid? Etc. No numbers. Usually in chemical reactions.
 Quantitative: Numerical part/Measurement

What are quantitative observations?
 Numerical part/Measurement
 Has Dimensions or Units
 Can mult/div, CAN'T add/subt quantities with different units
 Ex: 25.35 g ; 2 ft x3 ft = 6 "squared feet" > 6 ft^2

What are SI units?
 Systeme Internationale
 Based on Metric System

What are the SI units of Length, Mass, Time, Temperature, Energy, Volume?
 Length: meter (m)
 Volume: cubed meters (m^3)
 Mass: kilogram (kg)
 Time: second (s)
 Temp: Kelvin (K) = C + 273.15
 ANY Energy (SI): Joule (J)
 Heat Energy (Metric): Calorie (cal) = 4.184 J

Define Accuracy.
 How close to "correct" value.
 Trying to measure a standard.
 Calculated by Errors.

Define Error, Difference Error, and Percent Error.
 Error: Difference between your measurement and real value
 Ex: My measurement: C = 2.375x10^8 m/s Real: 2.998x10^8 m/s (speed of light)
 Difference Error: 0.623x10^8 m/s
 Percent Error: = (Diff Error/Correct) x 100
 Ex % Error: = (0.623x10^8 m/s)/(2.998x10^8 m/s) x 100 = 20.8 %

Define Precision.
 How repeatable/reproducible a measurement is.
 Ex: 24.275 g ; 24.286 g ; 24.279 g ; 24.263 g ; 24.273 g
 3 digits remain constant, 2 digits vary, first digit to vary is in 2nd dec. place
 # of CERTAIN digits + 1st UNCERTAIN (estimated) digit = # of significant digits
 4 significant digits

How do you find the number of significant digits/figures?
 1. Scan #'s from L > R until you reach 1st NONZERO digit
 2. Count the digits
 3. Watch for TRAILING zeros  Zeros that FOLLOW the nonzero digits
 Ex: 275.25 = 5 sig figs
 Ex: 0.00275.25 = 5 sig figs

What are Leading zeros?
 Come before nonzero digits
 They NEVER count
 Ex: 0.00037

What are Trailing zeros?
 Zeros following the nonzero digits
 If FOLLOWING the dec. point, ALWAYS significant
 Ex: 25.0 = 3 sig figs, zero is significant
 If BEFORE the dec. point, MAY be significant
 Ex: 250 = 2 sig figs, zero not significant; I know it's 200, not certain if it's 50
 Ex: 250. = 3 sig figs, zero is significant; I know it's 200, know it's 50, not certain if it's 0

How would you write 25,000 if you're certain of 20000 and 5000 and 1000's but not 10's?
 25,000 "4 sig figs"
 Scientific Notation: 2.500x10^4

Describe Scientific Notation.
 Convert a number to range between 1 and <10
 Ex: 250. = 2.50x10^2 ; (2) indicates # of dec. moves to the Left
 Ex: 0.00025 = 2.5x10^(4) ; (4) indicates # of dec. moves to the right; only 2 sig figs

Put these prefixes in order from least to greatest with their powers and symbols: mili, nano, centi, kilo, pico, mega, deci, micro.
 Pico (p): 10^(12)
 Nano (n): 10^(9)
 Micro (sexy u, "mu"): 10^(6)
 Mili (m): 10^(3)
 Centi (c): 10^(2)
 Deci (d): 10^(1)
 Kilo (k): 10^3
 Mega (M): 10^6

What are Unit (Conversion) Factors?
 Start with a known relationship and rearrange to make it a ratio.
 Ratios could be each other's inverses
 Ex: 1 ft = 12 in > (1 ft)/(12 in) = 1 => Converts to ft ; (12 in)/(1 ft) => Coverts to in
 EX: 240 in => ? ft
 (240 in)/1 x (1 ft)/(12 in) = 20 ft

What is Density?
 Ratio of mass to volume of matter
 Density = mass(g)/Volume(cm^3 or mL)
 Ratio of 2 quantities can be used as Unit Factor

What are the 2 types of Temperature scales and what do they include?
 Degrees Fahrenheit (F) and Degrees Celsius (C)
 Upper and Lower fixed points

What are Upper and Lower Fixed Points (UFP & LFP)? Of Celsius and Fahrenheit?
 LFP: Freezing point of water at 1 atmospheric pressure (atm)
 C = 0 degrees
 F = 32 degrees
 UFP: Boiling point of water " "
 C = 100 degrees
 F = 212 degrees

What is 1 division (of C/F)?
 1 increment (Degree) above the LFP
 180 div F = 100 div C
 Conversion factor => (9 div F)/(5 div C)
 Ex: Fries are 425 degrees F
 1. Subtract 32 (How far above LFP) = 393 div F
 2. Change to # div C by using conversion factor => 218 div C (degrees C)

What are the temperature conversion equations?
 Temp (C) = (5/9)(Temp (F)  32) => C = (5/9)(F  32)
 Temp (F) = (9/5)Temp (C) +32 => F = (9/5)C +32

