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The Effect of Sucrose Concentration on the Rate of Osmosis

Posted on Feb 15, 2024 by Danny

The Effect of Sucrose Concentration on the Rate of Osmosis

Potato and Carrot Slices Osmosis Lab Report

Are you looking for the best potato osmosis lab report help? You have come to the right place. Below is a full guide on how you can write your potato or carrot osmosis lab report.

Introduction

            The experiment aimed to explore the effect of sucrose solution concentration on the rate of osmosis in potato and carrot slices. The experiment used 5 different potato slices and 5 different carrot slices placed in a 0%, 25%, 50%, 75% and 100% concentrated sucrose solution. Each slice was named Red, Green, Blue, White and Yellow. The independent variable was the concentration of sucrose solution and the dependent variable was the change in mass.

Theory

            Osmosis is the movement of water particles from a low sugar concentration to a high sugar concentration through a semi-permeable membrane. Apart from sucrose solution concentration, other factors, such as temperature and the size of the particles affect the rate of osmosis. As the concentration of the sucrose solution is increased, the difference in mass of the potato/carrot increases. This is because the sucrose solution is a hypertonic solution indicating a high concentration of dissolved particles compared hypotonic solution with fewer dissolved particles. Besides, when a potato/carrot slice is placed in a solution with the same water potential, this is regarded as an isotonic solution. When a potato/carrot slice is placed in a concentrated sucrose solution that has a higher water potential, then, the water particles move from the potato/carrot slice to the solution. This results in a decrease in the final mass of the potato/carrot slice.

Hypothesis

            The hypothesis of this experiment is that (a) the mass of the potato/carrot slice will decrease when placed in sucrose solution with a higher water potential (hypertonic solution), (b) the mass of the potato/carrot slice will not change when placed in an isotonic solution and (c) the mass of the potato/carrot slice will increase when placed in a sucrose solution with lesser water potential (hypotonic solution).

Data Collection

Table 1: The Rate of Osmosis in a Potato Slice when placed in different concentrations of sucrose solution.

Sucrose concentration

Potato Initial Mass (g)

Potato Final Mass (g)

Red

Green

Blue

White

Yellow

Red

Green

Blue

White

Yellow

0%

Exp 1

3.32

3.11

2.95

2.96

2.97

3.81

3.65

3.41

3.17

3.38

Exp 2

2.87

3.06

3.03

2.88

3.03

3.34

3.52

3.50

3.30

3.55

25%

Exp 3

3.18

2.96

3.10

3.21

3.24

3.16

2.90

3.05

3.16

3.15

Exp 4

3.30

3.11

3.07

3.20

3.57

3.23

2.99

3.03

3.12

3.52

50%

Exp 5

2.91

2.89

3.22

2.79

3.09

2.36

2.38

2.49

2.17

2.49

Exp 6

3.10

3.41

2.83

2.91

2.84

2.41

2.60

2.12

2.21

2.24

75%

Exp 7

3.30

3.00

3.18

3.39

3.25

2.32

1.97

2.10

2.29

2.17

Exp 8

2.54

3.45

3.00

2.69

3.53

1.75

2.17

1.95

1.8

2.44

100%

Exp 9

2.70

2.89

2.49

2.60

2.66

1.81

1.90

1.56

1.51

1.63

Exp 10

2.82

3.33

3.09

3.47

2.80

1.80

2.30

2.02

2.08

2.01

 

Table 2: The Rate of Osmosis in a Carrot Slice when placed in different concentrations of sucrose solution.

Sucrose concentration

Carrot Initial Mass (g)

Carrot Final Mass (g)

Red

Green

Blue

White

Yellow

Red

Green

Blue

White

Yellow

0%

Exp 11

2.51

3.00

2.63

2.88

3.10

2.95

3.36

2.93

3.15

3.43

Exp 12

1.99

2.60

2.66

3.03

2.91

2.26

2.91

3.07

3.41

3.23

25%

Exp 13

3.54

3.71

3.54

3.28

3.37

3.37

3.79

3.65

3.32

3.40

Exp 14

3.30

3.42

2.86

3.22

2.79

3.30

3.48

2.92

3.31

2.92

50%

Exp 15

3.00

2.90

3.04

2.97

2.98

3.08

3.05

3.15

3.01

2.99

Exp 16

2.64

3.15

3.34

2.51

3.22

2.44

2.80

3.17

2.20

3.26

75%

Exp 17

3.98

3.32

3.58

3.40

3.53

3.41

2.83

2.88

2.91

2.90

Exp 18

2.98

2.99

2.69

3.72

2.90

2.40

2.36

2.28

2.91

2.29

100%

Exp 19

2.36

2.21

1.95

2.29

2.36

1.05

1.56

1.43

1.60

1.78

Exp 20

2.51

2.76

3.65

3.12

3.58

1.91

2.06

2.73

2.50

2.75

Data Processing

            This section processes the above-collected data. From the data collection results, both potato and carrot slices had different final masses compared to their initial mass. Hence, the change in mass can be calculated by subtracting the final mass from the initial mass. Besides, the percentage change in mass can be calculated by dividing the change in mass by the initial mass, then multiplying by 100. The average % change in mass will be calculated by adding the individual percentage changes in mass for Red, Green, Blue, White, and Yellow, then dividing it by 5.

Δ Mass = Final Mass – Initial Mass

Percentage Δ Mass = Δ Mass/Initial Mass * 100

The average percentage Δ mass = Total of % Δ mass for Red, Green, Blue, White, and Yellow/5.

Table 3: The change in mass and percentage change in mass for potato slices.

 

Red

Green

Blue

White

Yellow

 

Sucrose conc’n

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Average % change

0%

0.49

14.75

0.54

17.36

0.46

15.59

0.21

7.09

0.41

13.80

13.72

0.47

16.37

0.46

15.03

0.47

15.51

0.42

14.58

0.52

17.16

15.733

25%

-0.02

-0.62

-0.06

-2.02

-0.05

-1.61

-0.05

-1.55

-0.09

-2.77

-1.72

-0.07

-2.12

-0.12

-3.85

-0.04

-1.30

-0.08

-2.5

-0.05

-1.40

-2.24

50%

-0.55

-18.9

-0.51

-17.64

-0.73

-22.67

-0.62

-22.22

-0.6

-19.41

-20.17

-0.69

-22.25

-0.81

-23.75

-0.71

-25.08

-0.7

-24.05

-0.6

-21.12

-23.26

75%

-0.98

-29.69

-1.03

-34.33

-1.08

-33.96

-1.1

-32.44

-1.08

-33.23

-32.73

-0.79

-31.10

-1.28

-37.10

-1.05

-35

-0.89

-33.08

-1.09

-30.87

-33.43

100%

-0.89

-32.96

-0.99

-34.25

-0.93

-37.34

-1.09

-41.92

-1.03

-38.72

-37.04

-1.02

-36.17

-1.03

-30.93

-1.07

-34.62

-1.39

-40.05

-0.79

-28.21

-34

 

Table 4: The change in mass and percentage change in mass for carrot slices.

 

Red

Green

Blue

White

Yellow

 

Sucrose Conc’n

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Δ mass

% Δ mass

Average % change

0%

0.44

17.53

0.36

12

0.3

11.41

0.27

9.38

0.33

10.65

12.19

0.27

13.57

0.31

11.92

0.41

15.41

0.38

12.54

0.32

11

12.89

25%

-0.17

-4.80

0.08

2.16

0.11

3.11

0.04

1.22

0.03

0.89

0.51

0

0

0.06

1.75

0.06

2.10

0.09

2.80

0.13

4.66

2.26

50%

0.08

2.67

0.15

5.17

0.11

3.62

0.04

1.35

0.01

0.34

2.63

-0.2

-7.58

-0.35

-11.11

-0.17

-5.09

-0.31

-12.35

0.04

1.24

-6.98

75%

-0.57

-14.32

-0.49

-14.76

-0.7

-19.55

-0.49

-14.41

-0.63

-17.85

-16.18

-0.58

-19.46

-0.63

-21.07

-0.41

-15.24

-0.81

-21.77

-0.61

-21.03

-19.72

100%

-1.31

-55.51

-0.65

-29.41

-0.52

-26.67

-0.69

-30.13

-0.58

-24.58

-33.26

-0.6

-23.90

-0.7

-25.36

-0.92

-25.21

-0.62

-19.87

-0.83

-23.18

-23.51

 

Table 5: Standard Deviation for each Average Percentage change for Potato Slices.

Sucrose conc’n

 

Average % change

Standard deviation (g)

0%

Exp. 1

13.72

3.929556

Exp. 2

15.733

1.038785

25%

Exp. 3

-1.72

0.781252

Exp. 4

-2.24

1.034894

50%

Exp. 5

-20.17

2.179977

Exp. 6

-23.26

1.563094

75%

Exp. 7

-32.73

1.845157

Exp. 8

-33.43

2.645407

100%

Exp. 9

-37.04

3.575653

Exp. 10

-34

4.60143

 

            From the standard deviation results, Exp. 3 can be regarded as the most accurate experiment for the potato slices since it has the lowest standard deviation of 0.781252.

 

Table 6: Standard Deviation for each Average Percentage change for Carrot Slices.

Sucrose conc’n

 

Average % change

Standard deviation (g)

0%

Exp. 11

12.19

3.141437

Exp. 12

12.89

1.693321

25%

Exp. 13

0.51

3.095343

Exp. 14

2.26

1.690663

50%

Exp. 15

2.63

1.894279

Exp. 16

-6.98

5.418538

75%

Exp. 17

-16.18

2.385162

Exp. 18

-19.72

2.640663

100%

Exp. 19

-33.26

12.63401

Exp. 20

-23.51

2.225071

 

            From the standard deviation results, Expt. 14 can be regarded as the most accurate experiment for the carrot slices since it has the lowest standard deviation of 1.690663.

Table 7: Average % change in mass for potato and carrot slices for each sucrose solution.

Sucrose Conc’n

Average % Mass (Potato)

Average % Mass (Carrot)

0%

14.7265

12.54

25%

-1.98

1.385

50%

-21.715

-2.175

75%

-33.08

-17.95

 

Graph 1: The effect of sucrose solution on the average percentage change in mass of potato and carrot slices.

 

Conclusion

            To conclude, it is evident that the percentage of sucrose concentration affects the rate of osmosis. The experiment used 5 different potato slices and 5 different carrot slices. The different slices were named Red, Green, Blue, White, and Yellow. Each of the slices was subjected to 0%, 25%, 50%, 75%, and 100% concentrated sucrose solutions.

            The effect of sucrose solution on the rate of osmosis was cleary evident for 0%, and 100% concentrated sucrose solutions. For 0% concentrated sucrose solutions, the slices tended to gain more weight compared to 100% concentrated sucrose solutions where the slices lost weight. Besides, for 0% and 100% concentrated solutions, a substantial percentage change in mass was observed.

            These observations are in line with the osmosis principle that states that an increase in the concentration of sucrose solutions increases the water potential of the potato’s particles. As a result, water moves out of the potato particles towards the concentrated solution.

Evaluation

  • The different potato and carrot slices used could have a different amount of nutrition which would affect the rate of osmosis.
  • Sugar surrounding the slices might not be equally distributed resulting in different working scenarios for each slice.
  • The rate of osmosis could have been affected by the varying temperatures of the surroundings resulting in different results.

References

Phuntsho, S., Sahebi, S., Majeed, T., Lotfi, F., Kim, J. E., & Shon, H. K. (2013). Assessing the

major factors affecting the performances of forward osmosis and its implications on the desalination process. Chemical Engineering Journal231, 484-496.

Winfield, B. A. (1979). A study of the factors affecting the rate of fouling of reverse osmosis

membranes treating secondary sewage effluents. Water Research13(7), 565-569.

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Memory usage: 6.00Mb (6 291 456)
Timer [Time: 0.20587] [Mem.: 6.00Mb]
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Warning: Declaration of iaMailbox::getMessage($messageId) should be compatible with abstractCore::getMessage()
in file plugins/privatemessages/includes/classes/ia.front.mailbox.php
Backtrace91422 [8]
 
Unknown error type [8192]: The each() function is deprecated. This message will be suppressed on further calls
on line 75 in file includes/smarty/sysplugins/smarty_internal_compilebase.php
Backtrace14305 [15]
 
Error [2]
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includes/classes/ia.core.smarty.php on line [341]89476
Notice:
Lateness resource inclusion: //custompaperswritinghelp.com/plugins/testimonials/templates/front/css/style.css?fm=1590510938
Debug [1]