10 Cm 3 Of A Concentrated Solution example essay topic

442 words
Biology coursework Investigation of osmosis in potato tissue AIM. To investigate the effects that occur by osmosis on potato tissue Hypothesis I believe that the higher the concentration of sugar solution, the mass of the potato decreases yet I believe that after 0.4 the mass decreases. Scientific knowledge A biochemical process in living cells, that occurs with the movement of water. It can be deemed as the movement of water from a high concentration to a lower concentration, the diffusion down a water potential gradient across a partially permeable membrane.

This will continue until and equilibrium has been reached. A cell, in a lower water potential than its contents leaves by osmosis causing it to become flaccid. A cell, in a higher concentration than its potential water enters by osmosis and the cell becomes turgid. Independent variable Factors needed in the experiment that I must change fully answer my hypothesis. For my practical I will need to keep changing the concentration of each solution.

Therefore I will use 5 different types, 0 m, 0.3 m, 0.5 m, 0.7 m, and 1 m. I will test each conc. 3 times to check for anomalies and be able to give clear results. Shown below is a table telling how I will make the solutions. Conc. Of solution Sugar percentage Water percentage 0 m 0 10 3 m 3 7 5 m 5 5 7 m 7 3 1 m 10 0 Dependent variable The change in mass is how I will be able to fully answer my hypothesis constantly measuring the mass before and after the test.

Constant variable To make the practical fair I need to keep certain factor the same, such as vol. Of solution as it must be kept constant i.e. 10 cm 3, this means if it is changed then osmosis might not be able to fully reach its equilibrium. Also I must measure the length of each potato chip to 3 cm to keep the test fairer. Method Firstly I cut a 3 cm chip of potato and place it in 10 cm 3 of a concentrated solution that I made myself.

I measure the mass of the potato before the test and then place it in the test tube, which has a certain concentration. After a set amount of time I take the potato out of test tube and again weigh the potato. I repeat this process 15 times, with different concentrations. The control that I will be using in this experiment will be 0 m.