Vanessa Tsao, Lovette To, Wang Yeyun, Zhang Shenjia, Alicia Mak
Class 101, Nanyang Girls’ High School, 2 Linden Drive, Singapore 288683
In this project, the relationship between the concentration of salt solution and the length of the potato strip that was immersed in it was investigated. Five strips of potato of the same length were placed in different Petri dishes that contained water of different salt concentration. They were left for twenty minutes and the length of each potato strip was recorded after the experiment. The experimental results show that the length of the potato strip increased when placed in water of 0%, 2% and 4% salt concentration while the length of the potato strip decreased when placed in water of 6% and 8% salt concentration, indicating that the salt concentration of the potato strip is between 4% to 6%.
Osmosis takes place from an area of less negative water potential to an area of more negative water potential. However, the water potential of the potato strip may not be zero, hence osmosis may either occur from the potato strip to the solution or vice versa.
It is hoped through the experiment, the effects of osmosis of different stages on the potato strips would be explained, hence getting a better understanding of osmosis and its effect. It is also hoped that from the experiment the method to knowing the water potential in a certain object.
The hypothesis is: If the length of the potato strips is related to the concentration of the salt solution, then increasing the concentration of salt solution will decrease the length of the potato strips.
-Scalpel -5 strips of potato
-15cm ruler -0% salt solution
-White tile -2% salt solution
-5 Petri dishes with covers