Investigating Whether a Sugared Solution Has an Effect on Potatoes

Investigating Whether a Sugared Solution Has an Effect on Potatoes

Length: 2844 words (8.1 double-spaced pages)

Rating: Excellent

Open Document

Essay Preview

More ↓
Investigating Whether a Sugared Solution Has an Effect on Potatoes

Osmosis is the passage of water molecules from a weaker solution into
a stronger solution through a partially permeable membrane.

In this case, Osmosis applies to our practical because we are trying
to see if a sugared solution (sucrose) has an effect on potatoes. I
aim to investigate the effect of varying concentration of a certain
sugar solution on the amount of osmotic activity between the solution
and a potato chip of a given size. I will also endeavour to find the
exact (or as near as possible) concentration of sucrose solution when
no osmosis occurs and the concentrations are equal.

Preliminary Work

In a sense, preliminary work is as important as the actual experiment.
It allows you to make hypotheses before performing actual tests.

For my preliminary work, I used a 50 mm piece of potato. It was easy
to cut 50 mm (using a Vernier calliper) and to weigh them (using
electronic scales to two decimal places). We used 10 mls of sugar
solution/distilled water- this was the amount needed to cover one
piece of potato. This was put in a test tube along with a piece of the
potato and these were then put in a test tube rack. The first thing we
needed to observe was how different concentrations affected the weight
and length of the potato. We therefore needed to observe each end of
the spectrum. We tried 0.0 molar concentration (the lowest) and 0.8
molar (the highest.)

We then left each test until the next lesson, and then took the
measurement of the potato chips once more. This is my results table:

Concentration

Initial length

Final Length

Percentage difference

Initial mass

Final mass

Percentage difference

0 molar (water)

5 cm

5.15 cm

3 %

1.69 g

1.76 g

4.14 %

0 molar (water)

5 cm

5.2 cm

4 %

How to Cite this Page

MLA Citation:
"Investigating Whether a Sugared Solution Has an Effect on Potatoes." 123HelpMe.com. 24 Feb 2020
    <https://www.123helpme.com/view.asp?id=121005>.

Need Writing Help?

Get feedback on grammar, clarity, concision and logic instantly.

Check your paper »

Investigating Osmosis in Potatoes at Different Concentrations of Sucrose Solutions

- Investigating Osmosis in Potatoes at Different Concentrations of Sucrose Solutions Planning Aim: The aim of this experiment is to find out how solutions of different strength affect the osmotic movement. Preliminary work: For the preliminary work, I did a try out test to see if the method I had works. Also, I wanted to use the results I have after completing the experiment so that I can have an overview of how sucrose solutions of different strengths affect the diffusion of water in potato chips....   [tags: Papers]

Free Essays
2740 words (7.8 pages)

Investigating Whether the Strength of a Salt Solution Affect Osmosis in a Potato

- Investigating Whether the Strength of a Salt Solution Affect Osmosis in a Potato Factors ======= Factors that could affect the experiment: - · Temperature of water · Type of potato · Amount of solution · Amount of time the potato is in the solution Factors that I will change in my investigation: - · Percentage of salt in solution Preliminary Equipment ===================== 7 Beakers (250ml) 7 strengths of sugar solution (100ml of each strength) as follows 1x 0.0% salt 1x 0.5% salt 1x 1.0% salt 1x 1.5% salt 1x 2.0% salt 1x 2.5% salt 1x 3.0% salt Potato Ruler Cork Borer Knife Preliminary Plan...   [tags: Papers]

Free Essays
809 words (2.3 pages)

Investigating The Effect Of Concentration Of Salt Solution On The Mass Of Potato Chips

- Investigating The Effect Of Concentration Of Salt Solution On The Mass Of Potato Chips Aim: The aim of this investigation is to see whether the amount of salt solution affects the mass of the potato chip Hypothesis: In the solution below, water will diffuse from the dilute solution into the concentrated solution through the process of osmosis. Therefore the dilute solution level will fall and the concentrated level will rise Line Callout 2: Disapproved (is unable to go through the semi permeable membrane O Line Callout 2: Approved (is able to go through the semi permeable membrane P Salt solution Water [IMAGE] When a substance such as salt di...   [tags: Papers]

Free Essays
953 words (2.7 pages)

Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells

- Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells Aim: To investigate whether the different concentration of sugar solution will affect the weight and size of the potato cells. General background information: Osmosis is defined as the movement of water or any other solution's molecules from an area in which they are highly concentrated to a region in which they are less concentrated. This movement must take place across a partially permeable membrane such as a cell wall, which lets smaller molecules (E.g....   [tags: Papers]

Free Essays
3501 words (10 pages)

Investigating the Effect of Concentration of a Certain Salt Solution on the Amount Tissue of Potato Slices

- Investigating the Effect of Concentration of a Certain Salt Solution on the Amount Tissue of Potato Slices Aim: The aim of the experiment is to investigate the effect of concentration of a certain salt solution on the amount tissue of potato slices. Osmosis is the movement of a solvent (e.g. water) through a semi permeable membrane, from a solution that has a lower concentration of solutes (e.g. salt) to one that has a higher concentration of solutes. In osmosis, the membrane does not allow the solute to pass through, but does allow the solvent to pass through....   [tags: Papers]

Free Essays
1438 words (4.1 pages)

Investigating the Effects of Varying Sugar Concentration on the Amount of Osmotic Activity Between the Solution and Potato Tubes

- Investigating the Effects of Varying Sugar Concentration on the Amount of Osmotic Activity Between the Solution and Potato Tubes Hypothesis: Osmosis is defined as the net movement of water molecules from a region in which they are highly concentrated to a region in which they are less concentrated. This movement takes place across a partially permeable membrane e.g. a cell wall. This means that the cell wall will let smaller molecules such as water through but does not allow bigger molecules to pass through....   [tags: Papers]

Free Essays
1264 words (3.6 pages)

Investigating the Effect of Different Concentrations of Sugar Solutions on Potato Chips  

- Investigating the Effect of Different Concentrations of Sugar Solutions on Potato Chips   Aim: -   To investigate the effect on potato chips in different concentration of sugar solutions.   Introduction: -   Osmosis is the net movement of water molecules from a region where there is a higher concentration of water molecules to the region where there is lower concentration of water molecules. The water molecues move through a partially permeable membrane, which allows the smaller molecules to pass but not the big ones....   [tags: Papers]

Free Essays
1679 words (4.8 pages)

Investigating the Movement of Osmosis through a Selectively Permeable Membrane

- Investigating the Movement of Osmosis through a Selectively Permeable Membrane My aim for this experiment is to see the percentage increase decrease and results of potato tissue's mass difference, when placed in different concentrations of sugar solutions. This investigation would expect to have 3 different variables, Independent, which you can change, the thing that I will be changing in this investigation for the factors affecting osmosis, is the concentrations of the solution that changes the mass and investigate osmosis with potato tissues....   [tags: Papers]

Free Essays
1314 words (3.8 pages)

Essay about Investigating Osmosis in Potatoes

- Investigating Osmosis in Potatoes Preliminary Experiment Aim The aim of this experiment is to determine the solute concentration of potato tissue; i.e. To investigate at which point the sucrose concentration is the same as the solute concentration inside the potato (an equilibrium is reached) Introduction Osmosis is the movement of water molecules from an area of high concentration; (a weak solution), to an area of low concentration; (a strong solution), through a partially permeable membrane....   [tags: Papers]

Free Essays
2033 words (5.8 pages)

Investigating Potatoes Essay

- Investigating Potatoes Introduction In this scientific investigation I am researching what has happened to Mr Davies's potatoes. During the winter storms a few years ago a sea wall protecting Mr Davies's potatoes was breached causing his land to flood. Mr Davies's is now worrying about his crop as it's producing a poor quality and low yield. I intend to explain to Mr Davies via the use of experiments what has happened to his potatoes....   [tags: Papers]

Free Essays
1117 words (3.2 pages)

Related Searches


1.63 g

1.70 g

4.29 %

0 molar (water)

5 cm

5.2 cm

4 %

1.72 g

1.79 g

4.07 %

0.8 molar sucrose solution

5 cm

4.6 cm

-8 %

1.68 g

1.05 g

-37.50 %

0.8 molar sucrose solution

5 cm

4 cm

-20 %

1.72 g

0.97 g

-43.60 %

0.8 molar sucrose solution

5 cm

4.1 cm

-18 %

1.64 g

0.98 g

-40.24 %

This showed us that the experiment would work even if the percentage
difference were small with the distilled water; it still worked, as
one would logically predict. These are not the actual results that I
obtained: they are those of another group because the results that I
took went wrong and I will amend the errors that I incurred in my
final experiment: such as drying the chip too vigorously on paper
towel. When we were carrying out this preliminary work we found that
it would not be time efficient or accurate to measure the length of
the chips therefore I believe that we will just be measuring the
change in mass.

Method

Equipment:

One Potato

Test tubes

Test tube racks

Glass rod

1 molar sucrose solution

Distilled water

5 mm borer

White tile

Knife

Electronic scales

Vernier calliper

Forceps

Procedure:

Firstly, several potato chips (undeterminable number as I am
accounting for errors) will be taken out of the potato using the 5 mm
borer. They will then be measured using a Vernier calliper (named
after Pierre Vernier (1580-1637), a French mathematician) and cut to
50 mm in length. Each of these pieces will then be weighed (so that
there is something to compare the results to) using an electronic
scale (for accuracy) and their individual masses recorded to two
decimal places. The concentrations will then be made for the first
stage (three of each concentration) and each test tube will be
labelled with the concentration that it contains. A potato chip with
then be placed into each and the test tubes placed in the test tube
racks. This first stage tests will then be left until the next lesson
(most likely over night). Each piece of potato will be removed using
forceps, blotted gently on a piece of tissue paper (to remove excess
water on the exterior of the potato chip that may effect the weight
and therefore the results) and weighed and measured once more. These
measurements of length and mass will also be recorded in the table to
be analysed.

Fair Test:

Many variables effect osmosis. These variables include:

* Temperature

* Volume of sugar solution

* Concentration

* Weight of potato

* Surface area

To create a fair test certain characteristic of the experiment will
have to be kept the same whilst one key variable is altered (surface
area, concentration of solution, temperature are all key variables as
these are the ones that effect the amount of osmosis that will occur).
It has been chosen to vary the concentration of the sucrose solution:
the concentration will be measured in molars: this will then become
the independent variable.

To make sure this is a fair test I will have to keep all the variables
constant apart from the concentration. If I did change one of these
variables, say surface area: if one potato chip were 1 cm longer than
the other there would be more surface area for osmoses to occur,
therefore the test would not be fair. If I altered the temperature
osmosis would also be effected: the warmer most atoms are the more
quickly they move, therefore,
increased temperature will increase the rate of osmosis. The starting
weight (mass) of the potato chips is something that is going to be
difficult to get exact as even though they will be cut with the same
Borer and cut to the same length, there will be a slight variation in
density of the potato or some other unavoidable anomaly may make the
potato chips weight slightly different amounts. Even though mass is a
variable that cannot be ignored, for the purpose of this experiment it
is not crucial as I will be measuring the alteration in mass in
percentage and not comparing mass directly. The volume of sugar
solution in whatever concentration has been standardised to 10 cm3: if
it was more it would not matter but if it were to be less then It
might not cover the chip completely and therefore osmosis would be
hindered as there would be less of a surface area as some of the chip
would not be in the solution.

To make sure the experiment remains fair I will do all my experiments
at room temperature (approximately 20°C (any other temperature would
be difficult to maintain and may effect results), use the same type of
potato, which will be kept at the same size (length and width)) and
weight and have been treated in the same way. I will also use the same
volume of the solution in the test tube is kept fair. I will use an
accurate electronic balance in this experiment, to make certain even
small changes in mass are recorded. I will also keep using the same
balance (if possible) throughout the experiment so the measurements do
not vary due to any change that may be introduced by different scales.

Range of Values:

We are going to be given enough sucrose solution to do five different
concentrations (repeating each three times and taking an average to
improve accuracy) and one of just distilled water: but as we will aim
to find the solution that has the same concentration of water
molecules as potato tissue, our experiment will have to be done in two
stages. In the first stage we will us the concentrations:

0.0 molar (distilled water)

0.2 molar

0.4 molar

0.6 molar

These concentrations were chosen because in our preliminary results we
found that 0.8 molar was going to be to high (too far off (the
percentage was a large decrease) the aim of finding the exact
concentration of water molecules inside the potato) and that 0.0 molar
was too low (the percentage increase was not too far off 0 % change
but logically water would be a little way off the aim of 0 %): we
decided to go up in 0.2 of a molar because that way we could cover a
wider range with our limited resources: we are still going to do 0.0
molar as a sort of control (it also does not use up any of our
allowance of sucrose) The concentration that has the closes to 0 %
alteration in length and mass will be the basis for stage two of the
experiment. Whatever this concentration may be, we will try the
concentrations either side of it to attempt to determine the solution
that has the same concentration of water molecules as potato tissue
and no osmosis will occur. How far either side will be determined when
stage one has been carried out and the results analysed.

Prediction

Osmosis is defined as 'the movement of water molecules from an area of
high water concentration to an area of low water concentration, across
a semi-permeable membrane' (Collins, 1999). In a low concentration of
water the amount of solute (e.g. sugar) is high. This could be called
a strong or concentrated solution. When two such solutions are divided
by a semi-permeable membrane the water will move from the area of high
concentration to the area of low concentration, until both sides are
equal (have reached equilibrium).

[IMAGE]

This can be seen in living cells. The cell membrane in cells is
semi-permeable and the vacuole contains a sugar solution. So when a
cell is placed in distilled water (high water concentration) water
will move across the semi-permeable membrane into the cell (lower
water concentration) by osmosis, making the cell swell. This cell is
now referred to as turgid. If done with potato cells the cells would
increase in length volume and mass because of the extra water.

[IMAGE]

If these potato cells were placed in a solution with a low water
concentration, then the opposite would happen. Water would move out of
the cell into the solution. In extreme cases the cell membrane breaks
away from the cell wall and the cell is referred to as plasmolysed.
The potato cells will have decreased in length, volume and mass.

The greater the concentration of water in the external solution the
greater the amount of water that enters the cell by osmosis. The
smaller the concentration of water in the external solution the
greater the amount of water that leaves the cell.

However, there will be a point where the concentrations of water
inside and outside the potato cells are equal (isotonic). At this
point there will be no change in the length, volume and mass of the
potato, as the net movement of water will be zero, no osmosis has
occurred.

I predict that the higher the sugar concentration, the more water will
transfer from the potato into the sucrose solution making the potato
decrease in mass and length, and vice versa for a lower sugar
concentrations. I believe this will happen because the solution is
diluted with water; the water molecules will transfer over to the
stronger solution: whether this is the solution or the potato. Thus
occurring osmosis.

I also predict that if a sample floats in the solution then it will
gain weight and osmosise and if it sinks then the potato will
ex-osmosise.

Results Table

Concentration

Initial mass/ g

Final mass/ g

Percentage change in mass/ %

Average percentage change in mass/ %

0.0

1.04

1.20

+15.38

0.0

1.03

1.17

+13.60

0.0

1.01

1.18

+16.83

+15.27

0.2

1.03

1.08

+4.85

0.2

1.03

1.04

+0.97

0.2

1.01

1.03

+1.98

+2.6

0.3

1.00

0.98

-2.00

0.3

1.01

0.98

-2.97

0.3

1.04

1.00

-3.85

-2.94

0.4

1.03

0.92

-10.68

0.4

1.06

1.01

-4.75

0.4

1.03

0.96

-6.80

-7.41

0.5

0.96

0.81

-15.63

0.5

1.04

0.85

-18.27

0.5

1.05

0.86

-18.09

-17.33

0.6

1.01

0.76

-24.75

0.6

1.02

0.72

-29.41

0.6

0.97

0.74

-23.71

-25.96

[IMAGE]

Percentage change in mass =




Alterations to Planned Method

In my planned method I indicated that I would attempt to do my
experiment in two stages in order to get as closes as possible to the
aim of determining the concentration of water molecules inside a
potato chip. This was not actually feasible therefore we altered the
planned concentrations to the following six:

0.0 molar (distilled water)

0.2 molar

0.3 molar

0.4 molar

0.5 molar

0.6 molar

This allowed us to carry out the entire experiment in one go rather
than in two stages. This may have proven to make the final results
less accurate but it was more important to keep to the minimum amount
of time.

It was also unpractical as well as difficult to measure the length of
the potato chips as well as the weight therefore this was not done. I
do not believe that it will have effected the conclusions in any way.

Analysis of the graph and Conclusions

I believe the line of best fit for the point on the graph to be a
straight line; this shows that mass percentage loss and gain are
proportional to the concentration of sugar solution due to the fact
that the variable of concentration is not limited by other factors,
unlike the variable of temperature where too high or too low a
temperature might alter the potato in some way that was not desired
for the experiment. Therefore the graph shows that as the
concentration of sugar solution increases, the percentage change in
mass decreases going from a 15 percent increase when the potato chip
was in distilled water only, to a 26 percent decrease when the potato
chip was in a solution of 0.6 moles of sugar solution. This gives the
graph a definite negative correlation. This relationship is due to the
water molecules will transfer over to the stronger solution (moving
down the concentration gradient): whether this is the solution or the
potato. This is because the cell membrane in cells is semi-permeable
and the vacuole contains a sugar solution. So when a cell is placed in
distilled water (high water concentration) water will move across the
semi-permeable membrane into the cell (lower water concentration) by
osmosis, making the cell swell. When the potato chips were placed in a
solution with a low water concentration (high sugar concentration),
then the opposite would happen. Water would move out of the cell into
the solution. The selectively permeable membrane of the potato cells
allows water to move between the solution and the cells but not the
sugar, as the sugar molecules are too large to 'fit' through the
membrane.

Where my line of best fit crosses the x-axis, I believe to be the
amount at which the concentration of water molecules inside and
outside the potato cells are the same: the potato and the solution are
isotonic. On my graph this is given to be 0.24 Moles: this is when the
sugar solution is diluted with distilled water so that it is 0.24
moles in concentration. There is the possibility that a straight line
of best fit is incorrect and this would alter the amount.

I predicted that the higher the sugar concentration, the more water
will transfer from the potato into the sucrose solution making the
potato decrease in mass and length, and vice versa for a lower sugar
concentrations. I also predicted that if a sample floats in the
solution then it will gain weight and osmosise and if it sinks then
the potato will ex-osmosise.

The first part of my predication (When two such solutions are divided
by a semi-permeable membrane the water will move from the area of high
concentration to the area of low concentration, until both sides are
equal (have reached equilibrium), was accurate with my results and
graph as the more concentrated the sugar solution, the lower the
percentage change in mass was. The opposite is also true: that the
lower concentrations have a higher percentage change in mass. It was
not possible to predict what the concentration in moles would be where
the concentration of water molecules inside and outside of the potato
are equal because I only had a limited amount of data from my
preliminary experiment and that amount was not enough to predict or
educated guess at what the amount would be. The floating and sinking
of the potato chips was just a curious observation from the
preliminary experiment that proved to be more or less true within the
final experiment: some of the chips behaved in the predicted way but
there were some variations with some being half way in-between. There
was even discrepancy between potato chips in the same concentration of
sugar solution proving that not only the sugar solution is effecting
this. I believe that the way in which the potato chip is placed into
the test tube may have something to do with it as if it was stuck to
the side this may effect its 'floating rate'. There are of course many
other factors that could influence this but none are important to the
main point of the experiment.

The investigation has shown me that mass percentage loss and gain are
proportional to the concentration of sugar solution. I was not sure of
this before and could not predict anything from my preliminary work as
I only trailed two of the concentrations: not enough to do a basic
graph. The investigation has not proved with absolute certainty that
the concentration I have discovered for the water particle
concentration being the same both inside and outside the potato cell,
is absolutely certain and as I cannot find the exact information that
I am looking for through any other sources, I will have to be content
with my result and take into account experimental error.

Evaluation

I believe that the experiment produced reasonable results although
there were some differences within the concentrations, which could
have affected the final percentage, but as an average of the
percentage change was taken, I do not believe that it would have
altered it too much.

The drying of the potato chip to remove excess surface water may have
led to an inaccuracy in the results as there was no obvious way to
standardise this and therefore some of the chips may have been more
dry than others which would have lead to alterations in the weight.

There may have been an alteration in the temperature of the room that
we were not aware off that could have made the test unfair but it
would have been so slight that I doubt that it would have made much of
an impact.

If we had the time and resources to repeat the experiment another
three times, I believe that it would have been more accurate as any
anomalous readings would have been nearly compensated for by the
taking of an average from six results whereas from only three, an
anonymous reading may have still caused an average to be off.

The straight line on my graph is a line of best fit that only goes
through one point exactly (0.0) and another very nearly (0.2). The
other four are spaced approximately evenly either side of the line. I
believe that the line should have been truly straight with all off the
points on it but due to experimental error (error that is
undistinguishable) they are not in a line. There is one point (0.6),
which seems to be more off than the others but I cannot determine an
obvious cause of this error (although in my results table this is one
of two that had a great difference between percentage change in mass
in each of the run-throughs). There are no averages that are too far
out indicating that the results are fairly accurate: there is not too
much variability.

The results in my results table are fairly similar within the
concentrations with the maximum difference only being 5 percent
between runs in each concentration. I would have preferred if it was
less but there was not time to repeat the experiment over any more
times.

I am confident about my values, trend and therefore my conclusions to
the extent that I believe the negative correlation trend to be
accurate. I am not completely positive that a straight line is truly
the line of best fit and I am also not sure as to whether my line is
accurate as it is difficult to plot a straight line of best fit. If my
results were slightly different I may have decided to draw a curve but
then this would not fit in with the logic that mass percentage loss
and gain are directly proportional to the concentration of sugar
solution. I also had to round off my average percentage change in mass
to make it fit onto graph paper and also be easier to draw: two
decimal places were rounded off to one which has made my graph and
therefore possibly my conclusions less accurate.

To continue the experiment further I would like to have been able to
do more concentrations and to actually test out the conclusion that
there would be 0 percentage change with a solution of 0.24 moles. It
would also improve accuracy to have repeated the experiment with
perhaps different lengths and diameters of potato chips: as we are
measuring percentage change then the size would not matter if the
whole experiment was re-run with the same size and then the results
compared to the experiment which has been done.

Secondary sources include:

Biology lessons

Internet (various biology and coursework sites)

Encyclopaedias

Textbooks (various but mainly The Living World by Michael Roberts)
Return to 123HelpMe.com