Introduction:
In this experiment I will investigate osmosis in potato chips. I will
do this by placeing 3 different poatoes in 3 different solutions. One
will be pure water and the other 2 will be different concentrations of
salt solution. In this experiment I want to find out what will happen
to their masses. I will carry this experiment out over the time space
of an hour to give osmosis a chance to happen. I believe that the
method I am choosing to do is suitable because I will be able to
record what happens to the potato chip in the pure water and what
happens to the potato chip which is in the concetrated salt solution.
I will have recorded the mass at the beggining and at the end so i
will be able to work out the percentage change and see the diiference
in the change of mass. From this I will be able to observe in which
solution the potato will grow in mass and in which it will decrease in
mass.
Even before i have done the experiment, I am in a position to make a
predictio using my own knowledge of osmosis. I predict that the
potatoes in pure water will increrase in mass and the poatoes in the
salt solutions will decrease in mass and the potato which is in the
greatest salt solution will decrease in mass the most. I can make
these predictions now by using the theory of osmosis. The potato in
the pure water will grow in mass because the water concentration
outside the potato is greater than the water concentration inside. "
Osmosis is the movement of water molecules from a high water
concentration to a low water concentration through a partial permiable
membraine." Therefore i can back up my prediction by saying the
potatoes in the salt solutions will shrink because the concetration of
water inside the potato is greater than the water concentration
outside and therefore will decrease in mass because the water will
move from inside to the outside.
Investigate how the Concentration of Sucrose Solution affects the Mass of the Potato Chip Aim To find out how the concentration of sucrose solution affects the mass of the potato chip left in the solution for one day. Water Potential: The water potential of a solution is a measure of whether it is likely to lose or gain water molecules from another solution. A dilute solution, with its high proportion of free water molecules, is said to have higher water potential than a concentrated solution, because water will flow from the dilute to the concentrated solution (from a high potential to a low potential). Pure water has the highest possible water potential because water molecules will flow from pure water to any other aqueous solution, no matter how dilute. Prediction: Osmosis is the passage of water molecules from a weaker solution to a stronger solution, though a partially permeable membrane.
The Effect of Solute Concentration on the Rate of Osmosis Aim: To test and observe how the concentration gradient between a potato and water & sugar solution will affect the rate of osmosis. Introduction: Osmosis is defined as, diffusion, or net movement, of free water molecules from high to low concentration through a semi-permeable membrane. When a substance, such as sugar (which we will be using in the experiment we are about to analyse), dissolves in water, it attracts free water molecules to itself, and in doing so, stops them from moving freely. The effect of this, is that the concentration of (free) water molecules in that environment goes down. There are less free water molecules, and therefore less water molecules to pass across a semi-permeable membrane, through which sugar molecules and other molecules attached to them are too big to diffuse across with ease.
Potato and Osmosis Investigation PLANNING: (P) Some background Information: Water Potential and Living Plant Cells Plant Cells in Pure Water: If plant cells are placed in pure water (a hypotonic solution) water will initially move into the cells. After a period of time the cells will become turgid. Turgor pressure is the pressure exerted against the cell wall by contents of the cell. At first most water movement is into the cell. As the turgor pressure increases water will begin to diffuse out of the cell at a greater rate, eventually equilibrium will be reached and water will enter and leave the cell at the same rate.
I am going to carry out an experiment to measure the change in mass of
When doing this experiment I was able to see the effect of different concentrations on the rate of osmosis, each was done by measuring the initial mass and length of the potato cylinder and after osmosis, the results were conducted to show that as the sucrose concentration increases the rate of osmosis also increases as I said in my hypothesis thusly making a direct decrease in mass.
There is not really that much I can do to help make this experiment a
However, the solution could be more water than salt so the water from the solution could be more concentrated than the water inside the potato cells. If so then In theory the water in the solution should diffuse into the potato. cells and increase in mass. Apparatus: Potato to perform the experiment on. Thin metal tube to cut potato chops with.
If we put the potatoes in different concentrations of seawater (0%, .4%, .8%, 1.2%, 1.6%, and 2%) then the potato put in the highest concentration of seawater (2%) will begin to discolor and fall apart while the potato put in the lowest (0%) concentration of seawater won’t discolor and fall apart because the seawater with the 2% concentration will diffuse into the potato causing it to break down and discolor faster than the potato in the lower concentration of seawater.
Semi permeable membrane [IMAGE]Water molecules Salt molecules [IMAGE] Osmosis is the movement of water molecules across a semi permeable membrane from a region of high water concentration to a region of low water concentration. My prediction in this investigation is that the solution with the least salt will make the potato weigh more, thus the potato in the distilled water solution will weigh the heaviest, because there will be a higher concentration of water molecules in the distilled water than inside the potato cylinder. Therefore, water will move in from high concentration to low concentration this will increase the mass. I based my prediction on the process of osmosis, which is a special type of diffusion. It occurs across a permeable membrane, which allows some particles to diffuse through it and not others.
Influence of Temperature on the Activity of Potato Catalase Hypothesis That the higher the temperature the higher the reaction rate of potato catalyse to a point were denaturing occurs in the enzyme and the reaction rate of the potato catalase drops off. Prediction The rate of Catalase activity will be faster at higher temperatures until a point, because at higher temperatures there are more chances of collisions between the enzyme's (Catalase) active site and the substrate (hydrogen peroxide). However the rate depends on the active site being able to join with the substrate, and at higher temperatures the enzyme can be denatured, which changes the shape of the active site which thus prevents the reaction from happening. At first, as the temperature increases the activity of the Potato catalase also increases this is because the collision rate of the enzyme with the hydrogen peroxide is increased.
For my preliminary work, I used a 50 mm piece of potato. It was easy
Ø All the experiments have to be done by the same person on the same
When you place a potato chip in a salt or sugar solution, then if the
problem, formation of hypothesis, data collections by observing and experimenting. At all stages of the
Prediction I think that when the potato is placed in distilled water the potato mass will increase. This is because water, has, if pure, a weaker concentration than the potato, and the water molecules move in through a partially permeable membrane by osmosis. If the potato is in a high concentration salt solution, the potato mass will decrease because the potato is less concentrated than the salt solution, and the water will move through the partially permeable membrane into the stronger solution. However, if the potato mass stays the same after the experiment, this means that the water/salt solution and the potato must be of equal concentration.