ch1a

[More Chapter 1] 

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 * SI Unit for volume is the cubic meter
 * Many chemists, however, generally use smaller units of volume like the cubic centimeter or cubic decimeter
 * Another common unit for volume is the liter. [ liter : the volume occupied by one cubic decimeter ]

-Temperature Scales
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-Density
 
 * Density : mass per unit volume

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-Significant Figures
__**General Guidelines for Using Significant Figures**__
 * <span style="font-family: Tahoma, Geneva, sans-serif;">Any digit that is not a zero is significant. ( 845 cm has three significant figures and 1.234 has four significant figures, and so on)
 * <span style="font-family: Tahoma, Geneva, sans-serif;">Zeros between nonzero digits are significant. (606 m has three significant figures 40504 kg has five significant figures, and so on)
 * <span style="font-family: Tahoma, Geneva, sans-serif;">Zeros to the left of the first nonzero digit are not significant. Their purpose is solely to indicate the placement of the decimal point. (0.08 L has one significant figure, 0.000045 g has two significant figures, and so on)
 * <span style="font-family: Tahoma, Geneva, sans-serif;">If a number is greater than one, then all zeros written to the right of the decimal point count as significant figures. (2.0 mg has two significant figures and 3.040 g has four significant figures)
 * <span style="font-family: Tahoma, Geneva, sans-serif;">If a number is less than one, then only the zeros that are at the end of the number and the zeros that are between the nonzero digits are significant. ( 0.090 has two significant figures, 0.00420 has three significant figures, and so on)
 * <span style="font-family: Tahoma, Geneva, sans-serif;">For numbers that do not contain decimal points, the trailing zeros ( that is, zeros after the last nonzero digit) may or may not be significant. (400 cm may have one significant figure (the digit 4), two significant figures (40), or three significant figures (400) ) We cannot know which is correct without more information. Using Scientific Notation, however, can prevent this ambiguity.

<span style="color: rgb(255,0,89); font-family: Tahoma,Geneva,sans-serif;">-Accuracy and Precision <span style="color: rgb(0,255,0); font-family: Tahoma,Geneva,sans-serif;">
<span style="font-family: Tahoma, Geneva, sans-serif;">
 * <span style="font-family: Tahoma, Geneva, sans-serif;">Accuracy : how close a measurement is to the true value of the quantity that was measured
 * <span style="font-family: Tahoma, Geneva, sans-serif;">Precision : how closely two or more measurements of the same quantity agree with one another.

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<span style="font-family: Tahoma, Geneva, sans-serif;">Dimensional Analysis : the procedure used to convert between units in solving chemistry problems
 * <span style="font-family: Tahoma, Geneva, sans-serif;">based on a relationship between different units that express the same physical quantity
 * <span style="font-family: Tahoma, Geneva, sans-serif;">in general, a relationship is used in dimensional analysis : given quantity x conversion factor = desired unit
 * <span style="font-family: Tahoma, Geneva, sans-serif;">units are carried through the entire sequence of calculations. (if set up correctly, then all units will cancel except the desired one)
 * all this information was extracted from the Chang Chemistry textbook