Chemistry Lab

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Laboratory Techniques & Measurements

Observations from Procedures

Data Table 1 – Length measurements
Object|Length (cm)|Length (mm)|
CD|12|120|
Key|5|50|
Spoon|17|170|
Fork|19|190|
Metric Ruler|30|300|

Data Table 2 – Temperature measurements
Hot water from tap
(44ºC )|Boiling water
(70ºC)|Boiling water – 5 minutes
(100ºC)|
]111.2 F|158 F|212 F|
Cold water from tap
(24ºC)|Ice water
(5ºC)|Ice water – 5 minutes
(0ºC)|
75.2 F|41 F|32 F|

Data Table 3 – Mass measurements
Object|Estimated Mass (g)|Actual Mass (g)|
Pencil||5.8|
3 Quarters||17|
4 Dimes||9.1|
5 Pennies||12.5|
Key||7.2|
2 Quarters 2 Dimes||15.9|
1 Quarter 2 Pennies 1 DIme||13|

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|16.4|21.3|4.9|1||
alcohol||16.4|21|4.6|.786||

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|4.3|2.5|.5|.5|.625|6.88|

Data Table 6 – Displacement method
Object|Mass, g|Initial volume, mL|Final volume, mL|Object volume, mL|Density, g/mL| Magnet|4.5|8|9|1|4.5|
Metal bolt|8|8|10|2|4|

Data Table 7 – Archimedes’ method
Object|Mass, g|Mass of displaced water, g|Volume of displaced water, mL|Density, g/mL| Metal bolt |8|129.9|75|1.732|
Magnet|4.5|129.6|75|1.728|

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? Increased pressure could effect the boiling point.

B.An unknown, rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide. If the mass is 21.3g, what is this substance’s density? 20.74 (length x width x height)

C.A sample of gold (Au) has a mass of 26.15 g. Given that the theoretical density is 19.30 g/mL, what is the volume of the gold sample? 1.35

D.How did...
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