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YSTEM

It is equal to 39.37 in.
entimeter (cm.)
ecimeter (dm.)
eter (m.)
ilometer (km.)

dinarily used by the
centimeter; thus, the
level is recorded at
mm., and not 7 dm.

sed is the cubic centi

entimeter (cc.)

2

6

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The chemist uses only the cubic centimeter and the liter as measures of volume. Thus, the volume of a test tube is given as (say) 25 cc.; that of a flask as (say) 500 cc. or 0.5 liter.

3. Weight. The unit is the gram. This is the one thousandth part of the weight of a piece of platinum preserved at Sèvres, France. It is equal to 15.43 grains.

10 milligrams (mg.) = 1 centigram (cg.)

[blocks in formation]

The gram is practically the only unit used by the chemist. Thus, the weight of a crucible is given as (say) 10.532 g. and not 10,532 mg. or 10 g. 5 dg. 3 cg. 2 mg. Note that

1 pound troy: 5760 grains = 373.24 grams

=

1 pound avoirdupois =

1 U.S. quart = 0.95 liter

Also note that

1 centimeter =

7000 grains = 453.59 grams

nearly inch

1 kilogram = nearly 2 pounds (avoirdupois)

N-CENTIMETER SCALE

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