# Lab 1

Topics: Water, Oxygen, Hypothesis Pages: 2 (300 words) Published: May 25, 2014
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Exercise 1:
Dissolved oxygen is oxygen that is trapped in a fluid, such as water. Since virtually every living organism requires oxygen to survive, it is a necessary component of water systems such as streams, lakes and rivers in order to support aquatic life. The dissolved oxygen is measure in units of ppm—or parts per million. Examine the data in Table 2 showing the amount of dissolved oxygen present and the number of fish observed in the body of water the sample was taken from; finally, answer the questions below. Table 2: Water quality vs. fish population

Dissolved Oxygen (ppm)
0
2
4
6
8
10
12
14
16
18
Number of Fish Observed
0
1
3
10
12
13
15
10
12
13

1. Based on the information in Table 2, what patterns do you observe? The greatest number of fish observed is when the dissolved oxygen level is 12 ppm.

2. Develop a hypothesis relating to the amount of dissolved oxygen measured in the water sample and the number of fish observed in the body of water. If the level of dissolved oxygen is higher will more fish be present in the water sample.

3. What would your experimental approach be to test this hypothesis? The experimental approach would be to increase the level of dissolved oxygen and observe the fish activity.

4. What are the independent and dependent variables?
Independent variable- dissolved oxygen (ppm)
Dependent variable- fish

5. What would be your control?
Body of water

6. What type of graph would be appropriate for this data set? Why? A bar graph would be the most appropriate type of graph for this set of data because it is used to compare results that are independent from each other.

7. Graph the data from the table above.

8. Interpret the data from the graph made in Question 7.
Based on the data that was collect my hypothesis was refuted.

3B. 100 ml. Beaker ( in mm)
3C. Your Lab Box Lid: (in cm)