Chapter One
Physical Quanity                Name Of Unit             Abbreviation

Mass-                                kilogram                             kg
Length-                              meter                                 m
Time-                                second                                s
Temperature-                     Kelvin                                K
Electric Current-                 ampere                               A
Amount of Substance-         mole                                  mol
Luminous Intensity-            candela                               cd
The SI Units:
1. Nonzero Integers- always counts as sig figs

2. Zeros-
          a)  Leading zeros- precede all nonzero digits- do NOT count as sig figs
          b) Captive zeros- zeros between non-zero numbers- always count as sig figs
          c)  Trailing zeros- at the RIGHT END of the number- significant only if the number contains a decimal point
Rules For Significant Figures:
1. Carry extra digits through to final result, then round

2. If the digit to be removed is:
        a) less then 5, the number before it stays the same
        b) equal to or more then 5, the number before it is increased by 1 (one)
Rules For Rounding:
- To convert one unit to another, use the equivalence statement that relates the two units

- cancel unwanted units

- Multiply the quantity to be converted by the unit factor to give the quantity with the desired units

Example:

        
Convert 25.5 into centimeters:
(2.54cm = 1 inch)
                                  25.5 in x 
2.54cm64.8 cm
                                                  1 in
Converting:
Convert 98.6 F into Celsius and Kelvin:

       98.6- 32= 66.6
                               66.6F x 5/9= 37.0C
        37+ 273.15= 310.2 K
                                                      
C= 37.0 degrees
                                                        K=  310.2 degrees
Examples:
What is the density of a 15 g sample in 25 ml of liquid?
                  Density= mass/volume
                      
             
19.625g   = 0.7850g/ml
               25.00ml
                                                 
D= .7850
Example 2:
Example 1:
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