lab report 1

Cohesion and adhesion of distilled, tap, salt, and soapy H2O
Purpose: to test cohesion and adhesion of distilled H2O, tap H2O, salt H2O, and soapy H2O
Materials:
-pipet
-penny
-distilled H2O
-tap H2O
-salt H2O (see step 1)
-soapy H2O (see step 2)
-paper towel
Procedure:
1. To make salt H2O mix salt with distilled H2O
2. To make soapy H2O mix soap with distilled H2O
3. Place penny with the Lincoln side up on top of a piece of paper towel
4. Fill pipet with distilled H2O and hold it about 3 cm above the penny
5. Slowly drip the distilled H20 on the penny face and count the drips until the liquid leaks off the edge of the penny on to the paper towel
6. Record the amount of drips
7. Clean penny
8. Repeat steps 3 through 7, 3 more times substituting distilled H2O with tap H2O, salt H2O, and soapy H2O
Hypothesis: I think that the 10 drops of distilled H2O will fit on the penny because it seems that a drop of distilled H2O would take up a tenth of the penny face. 8 drops of tap H2O will fit on the penny because all the minerals in the water would take up some space and let less drops fit than distilled H2O. 6 drops of salt H2O will fit on the penny because salt granules take up more space than the minerals in tap H2O. 4 drops of soapy H2O will fit on the penny because the soap bubbles would take up more space than salt granules.
Data/obs.:
Group data (drops)
Trial
1
2
3
4
5
Avg.
Dist. H2O
55
26
34
51
32
39.6
Tap H2O
24
37
27
32
30
30
Salt H2O
26
56
35
35
41
38.6
Soapy H2O
35
13
23
19
20
22

Class data (drops)
Group
1
2
3
4
5
6
7
8
9
Dist. H2O
32.2
25
33
33.6
38.4
38.4
33.2
39.4
16.4
Tap H2O
33.6
43.6
32.8
35.6
38.8
38.8
27.8
16.6
13.2
Salt H2O
18.2
32.2
18.6
49.6
35.6
35.6
29.8
24
27.2
Soap H2O
22.8
17.8
13
23.6
17.2
17.2
20
15.8
18.8

Group
10
11
12
13
Dist. H2O
49
35.8
27.2
39.6
Tap H2O
61.8
19.4
28.2
30
Salt H2O
45.8
32.2