experiment 2 chem 106 PDF

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experiment 2 chem 106...

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Introduction Any chemical reaction that occurs in nature must obey the law of conservation of matter. This law states that matter is not created or destroyed in any physical or chemical process. However, this is not the same for volume. Intermolecular forces and molecular size greatly affect volume. The purpose of this experiment was to determine if volume is conserved the same way matter is. When substances of identical volumes are mixed together, the resulting volume is not always the same as the sum of the two volumes. Ethanol and water were mixed and then measured to see if there was a change in total volume. Materials 10ml graduated cylinder-used to measure solutions 25ml graduated cylinder-sued to measure solutions Water-liquid experimented on Ethanol-liquid experimented on Pasteur pipet-used to transfer small quantities of liquid Digital scale-used to weigh solutions and different pieces of apparatus Paper towels-used to dry apparatus Acetone- use to wash apparatus Beaker-used to hold solutions Lab manual-to record data

Observation and Experimental Part 1: Density of water Mass of empty 10ml graduated cylinder-25.48g Mass of 10ml water in 10ml graduated cylinder- 35.42g Mass of water 35.42g-25.48g=9.94g Density of water- D=m/v 9.94g/10ml= 0.994g/ml Part 1: Density of acetone Mass of empty 10ml graduated cylinder-25.48g Mass of 10ml acetone in 10ml graduated cylinder- 33.32g Mass of water 33.32g-25.48g=7.84g Density of ethanol- D=m/v 7.84g/10ml= 0.784g/ml

Part 2: Volume of solution with 10ml water and 10ml ethanol: 18.9ml

Part 3

Exp.

Volume water, ml

1 2 3 4 5

16.0 12.0 10.0 8.0 4.0

Mass cylinder + solution, g

Mass solution, g

Trial 1 Trial 2 Trial1

Volume ethanol, ml 4.0 8.0 10.0 12.0 16.0

Volume, solution, ml

Density, g/ml

Average density, g/ml

63.85 63.80 18.74

Trial 2 Trial Trial Trial Trial 1 2 1 2 18.69 19.6 19.3 .956 .968 .962

63.26 63.14 18.06

17.94 19.6

62.29 62.6 17.54 Volume %ethanol 61.35 61.49 16.97 0 20 60.47 60.41 16.09 40 50 60 80 100

19.4

17.45 19.5 19.6 Volume %water 17.11 19 100 80 16.03 19.2 60 50 40 20 0

.92 .90

19.1

.99

19.1

.83

.92

.92

.89 .895 Experimental density, g/ml .90 .945 .994 .962 .84 .835 .920 .895 .945 .835 .784

Expected density, g/ml .970 .932 .894 .875 .856 .818 .780

Expected density sample calculation Density= volume water*density water+ volume ethanol*density ethanol/ expected total volume 80%/100*.970+20%/100*.780=.932g/ml...