Laboratory Techniques & Measurements

Observations from Procedures

Data Table 1 – Length measurements
Object
Length (cm)
Length (mm)
CD
12
120
Key
5.2
52
Spoon
18
180
Fork
18.2
182

Data Table 2 – Temperature measurements
Hot water from tap
40(ºC )
Boiling water
95(ºC)
Boiling water – 5 minutes
95(ºC)

Cold water from tap
23(ºC)
Ice water
8(ºC)
Ice water – 5 minutes
40(ºC)

Data Table 3 – Mass measurements
Object
Estimated Mass (g)
Actual Mass (g)
Pencil
6
5.5
3 Quarters
16
16.9
5 Pennies
15
12.3
3 Dimes
10
9.1
Key
10
8.3
3 Quarters, 5 Pennies
35
30.6
Key, 3 Diimes
18
16.1

Data Table 4 – Volume measurements

Mass A
Mass B
Mass B-A

Liquid
Volume, mL
Graduated Cylinder, g
Graduated Cylinder w/ Liquid, g
Liquid
Density, g/mL
% error
Water
5
19.1
23.6
4.5
4.5/0 = 0.9
0.9*1=0.99 g/mL
Isopropyl Alcohol
5
19.4
23.1
3.7
3.7/5=0.74
0.74*0.786= 0.581 g/mL

Data Table 5 – Magnet – measurement method

Mass A
Mass B
Mass B-A

Object
Mass, g
Length, cm
Width, cm
Height, cm
Volume, cm3
Density, g/cm3
Magnet
4.1
2
0.5
0.5
0.3 cm3
4.1/0.5 =8.2

Data Table 6 – Displacement method
Object
Mass, g
Initial volume, mL
Final volume, mL
Object volume, mL
Density, g/mL
Magnet
4.1
7
8
1
4.1/1=4.1
Metal bolt
8.1
8
9.3
1.3
8.1/1.3=6.2

Data Table 7 – Archimedes’ method
Object
Mass, g
Mass of displaced water, g
Volume of displaced water, mL
Density, g/mL
Metal bolt
8.1
1.1
1.1
8.1/1.1=7.3
Magnet
4.1
0.8
0.8
4.1/0.8=5.1

Questions

A. Water is supposed to boil at 100°C. If the water in this experiment did not boil at 100°C, what could be the reason? The pressure of the atmosphere affects the degrees at which water boils. The purity of the water can