The Foundations of Chemistry

Volume

Volumes are often measured in liters or milliliters in the metric system. One liter (1 L)
is one cubic decimeter (1 dm^3 ), or 1000 cubic centimeters (1000 cm^3 ). One milliliter
(1 mL) is 1 cm^3. In medical laboratories, the cubic centimeter (cm^3 ) is often abbreviated
cc. In the SI, the cubic meter is the basic volume unit and the cubic decimeter replaces
the metric unit, liter. Different kinds of glassware are used to measure the volume of liq-
uids. The one we choose depends on the accuracy we desire. For example, the volume of
a liquid dispensed can be measured more accurately with a buret than with a small grad-
uated cylinder (Figure 1-13). Equivalences between common English units and metric
units are summarized in Table 1-7.
Sometimes we must combine two or more units to describe a quantity. For instance,
we might express the speed of a car as 60 mi/h (also mph). Recall that the algebraic
notation x^1 means 1/x; applying this notation to units, we see that h^1 means 1/h, or
“per hour.” So the unit of speed could also be expressed as mih^1.

Figure 1-13 Some laboratory

apparatus used to measure volumes

of liquids: 150-mL beaker (bottom

left,green liquid); 25-mL buret (top

left,red); 1000-mL volumetric flask

(center,yellow); 100-mL graduated

cylinder (right front,blue); and 10-

mL volumetric pipet (right rear,

green).

1-7 Units of Measurement 19

Figure 1-12 The relationship between inches and centimeters: 1 in.
2.54 cm (exactly).

TABLE 1-7 Conversion Factors Relating Length, Volume, and Mass (weight) Units

Metric English Metric–English Equivalents

Length 1 km 
 103 m1 ft
12 in. 2.54 cm 
1 in.

1 cm 
 10 ^2 m1 yd
3 ft 39.37 in.* 
1 m

1 mm 
 10 ^3 m 1 mile 
5280 ft 1.609 km* 
1 mile

1 nm 
 10 ^9 m

1 Å 
 10 ^10 m

Volume 1 mL 
1 cm^3 
 10 ^3 L 1 gal 
4 qt
8 pt 1L 
1.057 qt*

1 m^3 
 106 cm^3 
 103 L1 qt
57.75 in.^3 * 28.32 L 
1 ft^3

Mass 1 kg 
 103 g1 lb
16 oz 453.6 g* 
1 lb

1 mg 
 10 ^3 g1 g
0.03527 oz*

1 metric tonne
 103 kg 1 short ton
2000 lb 1 metric tonne
1.102 short ton*

*These conversion factors, unlike the others listed, are inexact. They are quoted to four significant figures, which is ordinarily more than sufficient.