2.  Every measurement device has its limitations  You can only estimate to between the lines, but not beyond.  Eg: a bathroom scale doesn’t give your weight to the thousandth of a pound  Eg: diagram in book, p 133  So we can only record measurements to the next level between the lines we can see, because we cannot visually estimate further.

3.  A beaker is never an accurate measurement device.  For accurate liquid measurement, use a…  Graduated cylinder  The liquid in a graduated cylinder may form a curve, called a …  Meniscus  When reading a graduated cylinder, always read the _______ of the meniscus  bottom

4.  Water freezes at 32 ˚F and boils at 212 ˚F  Water freezes at 0˚C and boils at 100˚C  As things cool down, particles slow down  The Kelvin temperature scale is based on absolute zero – a theoretical temperature at which electrons stop moving around nuclei and matter stands still  There is no such thing as a negative Kelvin  Kelvin is not stated as “degrees Kelvin”, but simply as “Kelvin”

5.  Each Kelvin unit is exactly equal to one Celsius degree.  0 Kelvin = -273˚C  Therefore 0 ˚C = 273 K  Add 273 degrees to Celsius to get Kelvin  Try these:  244 Kelvin = _______ Celsius  -29  Water boils at ________ Kelvin  373  Water freezes at ________ Kelvin  273

6.  How “packed” something is.  Loosely “packed” = low density  Tightly packed = high density  A derived unit. To calculate…  Mass ÷ volume  We love density  D = m/v  m = …  vd  v = …  m/d

7.  compares the density of something to the density of water at 4 ˚C (when water is the most dense)  specific gravity of water at 4 ˚C is 1.0  so, if an object floats, its specific gravity is (less than or greater than) 1?...  less than 1  if an object sinks, its specific gravity is > 1

8.  hand-out