Chem Chap 3 Review

Standard Metric Units

• mass- kilogram, kg
• volume- liter, L
• length- meter, m
• time- second, s
• temperature - Kelvin, K- neat thing about Kelvins no negative values, cannot get colder than absolute zero.

Weight- is the pull of gravity on an objects mass, therefore weight is dependent on gravity. Another way to look at this is an objects position, location, from a source of gravity. Farther away from gravity object will weigh less.

Density- is an intensive property of the object, that is it does not depend on the "amount" of the object. D=mass/volume. Be sure you can calculate for any variable in the density formula. Refer back to your worksheet for problems.

Factor-Label Method- be sure to review this. 100cm= 1m, therefore it also can be written:
1m/100cm or 100cm/1m.

Scientific notation

• when moving decimal to the right- negative exponent
• when moving decimal to the left- positive exponent
• after moving decimal only one number to the left of the decimal point.
• when multiplying add exponents, dividing subtract
  

ex: 0.0000045 4.5 x10 -6
450000 4.5 x10 5 ( -6 and 5 are exponents)
3 x 10 3 X 4 x 10 -6 12 x 10 3 +(-6) 12 x 10 -3 1.2 x 10 -2
8 x 10 4 / 2 x 10 -5 4 x 10 4 - (-5) 4 x 10 9

Significant Figures

Refer to rules in your notebook. In multiplication and division your answer can only have as many sig figs as the least precise number ( lowest number of sig figs)

ex. 0.001 1 SF
0.00100 3 SF
0.001001 4 SF
100 1 SF
101 3 SF
101.0 4 SF