Equipment:
1 3 5 6 7
2 4
Stop Clock
Cork Borer
- Cutting Tile and Paper Towels
- Cutting Knife
- 25cm Measuring Cylinder
- Distilled Water and 5xSmall Flasks
- Electronic Scales
Prediction:
For this experiment, I predict that
Method:
For this experiment on the investigation of Osmosis, I set up 5 small flasks of which in them I placed five different concentrations of Sucrose solution (see table below). I then cut five pieces of potato, from the same potato using the cork borer, and confirm that each piece of potato is the same length as each other. After I had done this, I placed the potatoes in the solutions at the same time and started the stop clock immediately. I then put the samples to one side and monitored the progress of the potato samples and noted any notes down for the experiment.
I choose a designated time to check the condition of the potatos after; the first time around I cj=hose to check my results after 20 minutes, and I then decided that I’d investigate to see if they was much, if any, deference between 20 minutes and 20 hours.
Fair Test:
Fair testing should play a big part in this experiment. If this experiment isn’t a fair test, we will be obtaining the wrong results, which could lead us to the wrong conclusions.
First of all, and most importantly, we will have to get the measurements and the weights of the solutions and the potatoes as exact, and as accurate as possible. We will try and get the measurements of the potatoes as accurate as possible for every single potato, evenly cutting the potato pieces, and making a record of the length to the nearest millimetre. And we will be using a very sensitive balance so that we can get the best readings possible.
But I believe one of the most important step in the fair testing is to make sure that the potato is fully covered by the solution. This is because the potato should fully submerge, by having total contact with the solution.
When using the balance, we will make sure that the balance is reading zero with the small foam bowl, before we put the 3 potatoes on it. This is so that we don´t get a false reading, with the weight of our potato with the reading it had before. And after the experiment, we will measure the 3 potatoes that should be dried as possible, and weigh it the same way, taking the reading to the nearest 2 decimal places.
And we will also be reading the measurements of the measuring cylinder by reading the bottom of the meniscus.
Carrying out the experiment in a constant temperature for the three hours of experiment is important. And to avoid temperature change, which might affect our 3 different sets of results, we will take the temperature of the solution into account.
Another important factor of a fair test is to start and stop the clock as quickly as possible. This meaning that we should start the clock as soon as the potato is put inside the flask, and stop the clock as soon as 20 minutes have passed. Stopping the clock, taking them out and measuring it all in less than a minute us quite impossible because we lack the number of balances. And there are obviously too many sets to go through at such a fast time. Therefore, we will try our best to weigh the potatoes as quickly and as safely as we can.
Getting and experimenting with the exact measurements of molars and water is vital to this task. If the volume of one solution in a test tube is higher or lower than another, will affect the pattern of results later on.
We will also make sure that the potato is fully covered by the 6 different kinds of solutions. This is because, is the potato isn´t covered up by the solutions, the effect of osmosis might not occur to the fullest.
Small things such as a dirty test tube, and a slightly cracked measuring cylinder could still affect the results, and therefore we will take these into consideration as well.
Safety:
Safety is an important aspect in every experiment, even if the experiment seems to be very harmless. And that is why we take this into consideration, no matter what.
We will be using a very sharp knife, which could injure someone if it’s not handled properly. And we will also be careful that the solutions don’t get into our bodies internally, just in case, because we are not fully aware of the damage it could do to us.
But other than that, there weren’t any bigger matters to be cautious of.
Results:
Analysis and Conclusion:
Evaluation:
