Experiment 2
Procedure A: Length Measurement
1. Length of a 13x150 mm Test Tube: There are several sizes of test tubes; they
are classified by their inside diameter in mm, and their length in mm.
2. Diameter of a Watch Glass: Watch glasses come in different sizes, too.
Diameter is the distance, through the center, across the watch glass.
3. Diameter of an Evaporating Dish: The diameter of an evaporating dish is the
distance, through the center, across.
Procedure B: Mass Measurement
1
or 0.1 grams. The
10
triple-beam balance below shows some examples.
Decigram Balances measure with a precision of
The measurement is 1.0 g.
The measurement is 0.5 g
This digital balance is a little more convenient:
Centrigram Balances measure with a precision of
1
or 0.01 grams
100
The measurement is 0.15 g
Here is 0.1
and here is 0.15 g
Milligram Balances measure with a precision of
and usually have a digital display as shown:
1
or 0.001 grams
1000
The objects you will determine the mass of are:
1. 13 x 150 mm Test Tube
2. 125 mL Erlenmeyer Flask
3. Crucible and Cover
Crucible & Cover
13 x 150 mm Test Tube
125 mL
Erlenmeyer Flask
Procedure C: Volume Measurement
The instrument you will you use to measure volume is the 100 mL
Graduated Cylinder. Test Tubes and Pipets are also shown in the figure below:
100 mL Graduated
Cylinder
Various Dropper
Pipets
13 x 150 mm
Test Tubes
Read from the bottom of the
meniscus and interpolate
between lines; here, the meniscus
is hard to see…
This measurement is between 46
and 47 mL… from the bottom of
the meniscus, it may be estimated
to be 46.5 mL.
On this buret
tube, you can
better see the
meniscus effect;
burets drain
liquid out, so
volume is
measured in the
opposite
direction… here,
the measurement
is: 43.30 mL
Procedure D: Temperature Measurement
25.0 °C
25.0 °C
25.0 °C
25.0 °C
Other materials needed for procedure D are
shown below:
Use D.I. Water for distilled water.
Wire Gauze
Deionized Water
(DI H2O)
Tap Water
Ring
Ring Stand
100 &
150 mL
Beakers
Bunsen
Burner
Thermometer
The ice machine is located near the
stockroom. Please keep the scoop on
top!
Procedure E: Mass and Volume of an Unknown Solid
These are the type of unknown solids available for this experiment:
Measuring the length, width, and height gives you values from
which you can calculate volume;but, you’ll need to remember
that 1 cm3 = 1 mL.
length
height
width
V=lxwxh