Osmosis and Diffusion Investigation
Aim: To examine the process of osmosis and diffusion.
Part A:
Step 1:
Q1.[IMAGE]
Q2. The jiggling motion is visible because the fat globules are
constantly being bombarded by smaller particles.
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Q3. The Brownian motion is the ‘jiggling’ motion of the milk fat
globules. All matter is in constant motion.
Step 2:
Q4. a) After 5 minutes
Clear uncoloured water
Cloud of purple stain
* Potassium Permanganate
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b) After 24 hours
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Potassium Permanganate
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The potassium permanganate will have spread throughout the beaker as
the water molecules are constantly moving around.
Step 3:
Q5. The salt that was placed on the egg turned into ‘sweat’ like
beads on the egg.
Q6. There is a higher water concentration inside the egg, causing the
water to travel through the egg to the salt. The salt creates osmotic
pressure on the water molecules in the egg. This causes the ‘sweat’
like beads on the egg.
Salt
Egg
Water
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Step 4:
Q7.
Before:
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Water
Sultanas
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After 24 hours:
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Bubbles of oxygen allow the sultana / grape to float
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Q8. There is a higher water concentration on the outside of the
sultana than the inside. The water flows into the sultana fairly
quickly which starts to push the sultana back into a ‘grape shape.’
The water concentration is now even on the inside and out. This
process is called osmosis.
Part B:
Aim: To investigate the action of a differentially permeable membrane.
Method: See attached.
Apparatus: See attached.
The water level in the cellulose bag rose because of the higher
When the eggs are dropped onto the pillow, the eggs will bounce a little and stay whole.
* We would have to leave one end open to fill it up with the different
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.
Investigate the factors affecting the rate of Osmosis Planning Osmosis is the diffusion of water from a lower concentration of solute to a higher concentration of solute, through a partially permeable membrane. In a high concentration of water the amount of solute (e.g. sucrose) is low. This could be called a weak or dilute solution. In a low concentration of water the amount of solute is high. This could be called a strong or concentrated solution.
cork borer; we made sure we cut off the edge with the skin on it, as
moves along the cells of the root and up the xylem to the leaf. Water
going in is the same as the amount going out, so there is no overall
When a piece of fresh beetroot is left to stand in a beaker of cold
when to do it etc. This should lead me to good results at the end of
0.2M, as there is too much weight loss at values below this for it to
Factors Affecting Osmosis The aim of this experiment is to investigate the factors affecting osmosis. I have chosen to investigate the effect varying concentration of sucrose solution has on the amount of osmotic activity between the sucrose solution and a plant cell. The plant cell I have chosen to use is a potato tuber from which I plan to cut potato chips of equal length which I will place in test tubes filled with varying concentrations at equal volumes of sucrose solution. After a set amount of time I will remove the potato chips and record the change in length.
Introduction: Diffusion is the movement of molecules from a higher concentration to a lower concentration. Imagine you had a glass of water and put a drop of food coloring in. The molecules of food coloring would move from the initial site of the drop, which has an high concentration of the coloring, to the rest of the water, which has a low concentration. Eventually, the food coloring will spread out so that the entire glass of water has an equal concentration of it. At this point, the glass of water is in dynamic equilibrium - that is, the average concentration of the food coloring throughout the water is the same. Molecules are always moving, so there will be times when the food coloring happens to converge on one spot and leads to a higher concentration. However, on average the concentration is relatively equal. Osmosis is similar to diffusion, in that it is the movement of molecules from a high to low concentration. However, there are two major differences. The first one is that osmosis is the movement of water exclusively - the movement of any other molecule besides it is not considered osmosis. The second one is that osmosis is the movement of water across a selectively permeable membrane. A selectively permeable membrane is one that allows certain molecules through and blocks others. Whether or not a molecule can pass through the membrane usu...
Equipment Potato, Borer, Beakers, Measuring Cylinder, Stopclocks, Distilled Water, Electronic Balance, Salt solutions of various concentrations. Diagram [IMAGE] [IMAGE] [IMAGE] When we leave the potato in the solution for the allocated time, water
Water will always move from a high y to a low y. y can be measured in
Osmosis is the movement of water from a higher concentration to a lower concentration across a membrane. Osmosis is considered to be a passive transport because energy is not required in order for water molecules to move in and out. It is semi-permeable and the reason being so is because not all different molecules can enter. It leaves certain solutes out and allows certain ones in. the purpose of this lab is to see how the use of diffusion can allow the osmosis to travel across the membrane. To start off there was a sample bag containing sodium Sulfate (NaSO4), and a big beaker of sodium chloride (NaCl). We placed each in testing tubes containing different solutes which were starch, sulfate ion, chloride ion, and protein and saw how they reacted in terms of osmosis (hypertonic, hypotonic,