So I will be able to tell if the potato chips gain or lose water I will weigh the chips before and after the experiment, if the chips gain weight then they will have taken in water and if they loose weight then they will have lost water. I will measure the chips on scientific scales which are very accurate and will be able to give an accurate reading.
I will test the chips in 6 different solutions and try each solution twice to get an average result. I will use 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 Molar sucrose solutions.
Each chip will stay in its concentration for exactly 1 hour, I will use stopwatches to make this as accurate as possible, also I will try to keep the temperature and mass of the chips and sucrose solutions the same each time.
Before I weigh the potato I will dry out the potato by dabbing it with a paper towel, this will stop the excess water from being weighed.
If the potato chips that I use are different mass or shape I will have to find out the percentage that each chip’s mass increases by and compare them.
Predictions
I think that when the concentration is low, 0.0, 0.1, 0.2, the mass of the potato will increase because the week solution will be able to pass though a semi-permeable membrane into a stronger solution making the chip gain weight. Whereas when the concentration is in the middle strength region, 0.3, 0.4, then the chips will start to keep the same weight because the sucrose concentration will star to equal out. Also I think that when the concentration is high, 0.5, the chips will start to loose weight because the sucrose concentration will be higher out side of the chip.
I think that the texture and strength of the chips will change as well; I think that when the concentration is low that the chips will stay strong or get stronger due to gaining mass, then when the concentration is In the middle then the chips will get softer and when the chip is in high concentration the chip will be soft and flexible.
I think that when the concentration is the lowest then the speed of osmosis will be at its fastest because the concentration outside the chip will be weaker than inside the chip allowing osmosis to be quicker.
Obtaining Evidence
Results
Analysis
Conclusion
The mass of the potatoes in each solution changes; in the 0.0 Molar sucrose solutions the mass increases by an average of 0.95g, this is because the sucrose solution is weaker than the concentration inside the chip. In the 0.1 Molar sucrose solutions the mass increases by an average of 0.11g, this is also because the sucrose solution is weaker than the concentration inside the chip. In the 0.2 Molar sucrose solutions the mass increases by an average of 0.05g, the gain is starting to get smaller here showing that the concentration inside and outside the chip are becoming equal. In the 0.3 Molar sucrose solutions the mass increases by an average of 0.095g which is also a very small increase showing that the concentration inside and outside if the chip is becoming equal. In the 0.4 Molar sucrose solutions the mass increases by an average of 0.05, which shows that the concentration will soon become more on the outside of the chip. In the 0.5 Molar sucrose solutions the mass increases by an average of 0.08, which is an increase of the last solution, this may be an anomaly as well as the average for the 0.3 Molar sucrose solutions.
Osmosis occurred fastest in the 0.1 Molar sucrose solution, this happened because the solution was quite week allowing it to pass through a semi-permeable membrane in the chip due to the high concentrated solution inside the chip.
Evaluation
By doing this experiment I was able to show the effect of concentration of sucrose on the speed of osmosis, this is shown in my results. Most of my results are as accurate as I think I could have got them, however there are a couple of results on the mass after where the mass after drops bellow the mass before at a weak concentration. These anomalies where probably caused by an increase in temperature or a slightly stronger solution than with the other results.
If I did the experiment again then I would do each concentration more than twice, probably three or four times each, this would give me a much more accurate set of results because I would get a much more accurate average and I would have enough results to ignore any anomalies.
