Density = Mass Volume

At 4oC one gram of pure water occupies one milliLiter or one cubic centimeter.

Calculations

1) 43.2 mL of liquid has a mass of 50.0 grams. Calculate the density of the liquid.

2) An empty graduated cylinder has a mass of 113.713 grams. When it contains 42.9 mL of liquid it has a mass of 150.607 grams. Calculate the density of the liquid in gm/cc.

3) A 89.967 g rock is placed in a graduated cylinder containing 44.9 mL of water. The new reading was 59.1 mL. Calculate the density of the rock in g/mL.

4) A 5.5 Kg block of metal imeasures 4.60 inches by 5.10 cm by 200. mm. Calculate the density of the metal in g/cc.

Density as a conversion factor

1) Calculate the mass of 300. mL of alcohol if it has a density of 0.80 g/mL

2) Calculate the mass of 150. mL of concentrated sulfuric acid. (density = 1.80 g/mL)

• Rounding off Numbers

Rules for Significant figures (zeros)

1) 123456789

2) 23.09

3) 1.2500

4) 0.000066

5) exact numbers

6) 22,200 22,200. 22,200.0

22 mm

Rule 4 revisited

Why Significant Figures???

Scientific Notation

0.000 000 000 000 000 000 000 00166 X 602 000 000 000 000 000 000 000

1000 = 10 x 10 x 10 = 103

100 = 10 x 10 = 102

10 = 101

1 = 100

0.1 = 1/10 = 1/101 = 10-1

0.01 = 1/100 = 1/102 = 10-2

0.001 = 1/1000 = 1/103 = 10-3

terameters

gigameters

megameters

kilometers

7.6 meters

millimeters

micrometers

nanometers

picometers

tera- (T-) 1012 1 trilliongiga- (G-) 109 1 billionmega- (M-) 106 1 millionkilo- (k-) 103 1 thousandhecto- (h-) 102 1 hundreddeka- (da-) 101 tenUnit of measuredeci- (d-)10-1 1 tenthcenti- (c-)10-2 1 hundredthmilli- (m-)10-3 1 thousandthmicro- (µ-)10-6 1 millionthnano- (n-)10-9 1 billionthpico- (p-)10-12 1 trillionth

Scientific Notation

0.000 000 000 000 000 000 000 00166 X 602 000 000 000 000 000 000 000