Scientific Method - lab work PDF

Preview

Summary

lab work...

Description

Faster Plop, Plop, Fizz, Fizz: A Scientific Method Investigation Austin Mikeal

Section 001

5/25/2021

1

Data Activity 1 1. State a hypothesis for Activity 1 using an “if/then” statement. Remember to create a statement that is able to be tested empirically. As the temperature of the water increases, the time it will take for the Alkaseltzer to dissolve will decrease.

Data Table 1 Run No.

Cup

1

Temp. (˚C)

Time (sec.)

Observations

C

6˚C

160 sec.

Middle time to dissolve for cold water

1

RT

20 ˚C

71 sec.

Longest time to dissolve for RT water

1

H

58 ˚C

13 sec.

Fastest time to dissolve for hot water

2

C

5 ˚C

161 sec.

Longest time to dissolve for cold water

2

RT

21 ˚C

67 sec.

Middle time to dissolve for RT water

2

H

53 ˚C

19 sec.

Longest time to dissolve for hot water

3

C

7 ˚C

158 sec.

Fastest time to dissolve for cold water

3

RT

23 ˚C

58 sec.

Fastest time to dissolve for RT water

3

H

54 ˚C

17 sec.

Middle time to dissolve for hot water

Avg.

C

6˚C

159.6 sec.

Cold water takes longest to dissolve

Avg.

RT

21.3 ˚C

65.3 sec.

Avg.

H

55 ˚C

16.3 sec.

© 2016 Carolina Biological Supply Company

RT water is in between hot and cold water times

Hot water is the fastest to dissolve

2 2. Using graphing software such as Excel®, graph the results of Activity 1. Please see the Introduction to Graphing manual for guidance.

3. What are the two variables that you graphed? The two variables that were graphed above were the temperature of the water the Alka-Seltzers put into and the time it takes for the Alka-Seltzers to dissolve. 4. Which is the independent variable? Should it be on the X- or Y-axis? Why? The independent variable in this experiment is the temperature of the water the Alka-Seltzers were put into and this should be placed on the x-axis because it is not affected by the time it takes the Alka-Seltzers to dissolve. 5. Which is the dependent variable? Should it be on the X- or Y-axis? Why? The dependent variable in this experiment is the time at which it took for the AlkaSeltzer to dissolve and should be placed on the y-axis because the temperature of the water the Alka-Seltzers are put into does have an affect on the time it takes for them to dissolve. 6. Predict how many seconds it will take to dissolve an Alka-Seltzer® tablet in 200 mL of water at the following temperatures. Use the exponential trend line to find the function used in predicting the time. If needed, please refer to the Introduction to Graphing manual for guidance. a. 35°C It would take around 40 seconds for the Alka-Seltzer to dissolve at 35°C. b. 60°C It would take around 15 seconds for the Alka-Seltzer to dissolve at 60°C.

© 2016 Carolina Biological Supply Company

3 c. 80°C It would take around 5 seconds for the Alka-Seltzers to dissolve a 80°C.

Activity 2 7. List five questions about the rate at which Alka-Seltzer® tablets dissolve if the temperature was held constant and one of the controlled variables was changed. Will the temperature in the room have an effect on how fast the Alka-Seltzer to dissolve? Will the amount of noise in the room have an effect on how fast the AlkaSeltzer to dissolve? Will the amount of light have an effect on how fast the Alka-Seltzer to dissolve? Will the amount of water in the cup have an effect on how fast the AlkaSeltzer to dissolve? Will the force of the wind have an effect on how fast the Alka-Seltzer to dissolve? 8. Develop a new hypothesis based on one of the questions. Remember that a hypothesis must be testable with empirical or measurable data. If the amount of water in the cup is changed, then I believe that the amount of time it takes for the Alka-Seltzer to dissolve will be the same as it would be if there was more water in the cup.

Activity 2 Table

State the hypothesis.

If the amount of water in the cup is changed, then I believe that the amount of time it takes for the AlkaSeltzer to dissolve will be the same as it would be if there was more water in the cup.

Identify the The independent variable is the amount of water that is present in the cup. independent variable. Identify the dependent variable.

The dependent variable is the amount of time it takes for the Alka-Seltzer to dissolve.

List the controlled variables.

The controlled variables include the temperature of water, amount of light in the room, noise level in the room, and force of the wind in the room.

© 2016 Carolina Biological Supply Company

4 How will the dependent variable be measured?

The dependent variable will be measured by a stopwatch or timer.

State the hypothesis.

If the amount of water in the cup is changed, then I believe that the amount of time it takes for the AlkaSeltzer to dissolve will be the same as it would be if there was more water in the cup.

If the hypothesis is true, what results are expected?

If the hypothesis is true, then the amount of time it takes for each Alka-Seltzer should remain the same.

© 2016 Carolina Biological Supply Company

5

Data Table 2 Run No.

Amount of Water

Time (sec.)

Observations

1

100mL

59 sec.

Shortest time for 100 mL

1

150mL

60 sec.

Longest time for 150 mL

1

200mL

61 sec.

Longest time for 200 mL

2

100mL

60 sec.

Middle time for 100 mL

2

150mL

58 sec.

Shortest time for 150 mL

2

200mL

60 sec.

Shortest time for 150 mL

3

100mL

61 sec.

Longest time for 100 mL

3

150mL

59 sec.

Middle time for 150 mL

3

200mL

60 sec.

Shortest time for 200 mL

Avg.

100mL

60

Avg.

150mL

59

Avg.

200mL

60.3

About the same time as the other two. About the same time as the other two. About the same time as the other two.

What could have been done in either activity to make the results more reproducible? There would be more reproducible results if human error were taken out of both experiments. Initial Set Up Photo:

© 2016 Carolina Biological Supply Company

6

Midway Photo:

Final Shot:

© 2016 Carolina Biological Supply Company...