Testable Question: If iodine diluted in water (iv and solvent) is put in a plastic baggie (control) how will diffusion occur while put in a beaker with diluted cornstarch (dv and solute)?
Background research: Iodine is an indicator for cornstarch and will turn purplish-black when reacting with it. In this case iodine is the solute and cornstarch is a solvent. Diffusion is where molecules go from an area of low concentration to high concentration until molecules are evenly spread out. Plastic is semipermeable and iodine is smaller than the pores in plastic while cornstarch and water are bigger.
Hypothesis: We hypothesize that the iodine will go from the plastic baggie to the cornstarch then back until it evens out as the iodine is smaller than the plastic baggies membranes , so it will fit through and go from the high concentration to low concentration in the beaker outside then come back to the baggie as the outside will have higher concentration until it evens out in the baggie and in the beaker. While the water and cornstarch cannot go through as their molecules are bigger than the plastic baggies membrane they will not traverse between the baggie and the beaker.
Materials: Plastic Baggie, Water, Iodine, Cornstarch, A spoon, Rubber Band
Procedure: 1 - Fill baggie until it is about ⅓ full. 2-Then add 20 drops of iodine and tighten it but using rubber band on top 3- Fill beaker halfway with water and add 2 tsp of cornstarch and start mixing with spoon. 4 - Put baggie in
After added, pick up the beaker and swirl it around lightly for a short period of time.
inside of the bag, and starch and water in the beaker? Why? The starch would stay in the beaker and the glucose and Lugol’s solution would be inside and outside of the bag. The glucose would then able to diffuse because the molecules are now small enough to pass through it.
Introduction: I know prior to doing this experiment that iodine mixed with starch creates a dark color and that most objects, organic and inorganic, naturally experience isotonic reactions.
1. The relationship between rate of diffusion/ osmosis, volume, and surface area can be easily seen and analyzed through the data that was collected from procedure one: Surface Area and Cell Size. Phenolphthalein is a dye-material in this lab that was used to determine whether a substance was an acid or base. This could be told as the phenolphthalein changed into a murky. Muddled and clouded color when mixed with acids. When the chemical aid was mixed in with a base, the color
In the rubber egg lab also known as the osmosis lab, I first measured the circumference of the egg which was 6 inches. The egg had no cracks and was hard. I placed the egg in the vinegar and within seconds the egg started to bubble. These bubbles were carbon dioxide. After 72 hours the shell of the egg had started to dissolve or flake. This would be considered passive transport as the vinegar diffused across the egg shell without any force. Seventy-two hours into the experiment the membrane was exposed, and had a circumference of 8 inches. Before the egg had a shell and you couldn’t see through it but once the vinegar acted as an acetic acid it broke down the shell and left a yellow membrane that felt like rubber this is an example of diffusion. I then placed the egg in another container and put corn syrup over the egg for 24 hours. The egg had shriveled and shrunk, the water had left the egg and went into the syrup and that is what caused the egg to shrink. The corn syrup is essentially pure sugar with very little water so the osmotic pressure is very low. I then placed the shriveled egg in water and waited for another 24 hours. After observation the egg had no
Filled two bags with three-quarters of water and one with the salt solution by using the pipette and the pipette pump. Closed carefully with the thread and cut the excess of bag or thread, make sure they are completely sealed before placing them in the beakers. The beakers should be labeled with the crayon and with a pen write down in the paper towel the contents of each beaker and bags respectively to avoid confusions, in the following order. 1) Bag 1 will be filled with distilled water and beaker 1 will be filled with two-thirds of 10% NaCl solution. 2) Bag 2 will be filled with 10% NaCl solution and beaker 2 will be filled with two-thirds of distilled water.
Diffusion is the transfer of molecules from an area that has a higher concentration to an area that has a lower concentration. Osmosis is the diffusion of water. The purpose of this experiment was to study the process of osmosis. In order to test osmosis, eggs that had been soaking in vinegar were taken and placed in four beakers of solution with different levels of glucose. Using this experiment we were able to determine the rate of osmosis of different solutions, with various amounts of glucose, through eggs. In the results of this lab it was found that the eggs were either hypertonic or hypotonic and that the
Submerge the graduated cylinder in the plastic tub so that it is completely filled with water. Hold the open end of the graduated cylinder and move it vertically upside-down where the open end of the graduated cylinder is still submerged in the plastic tub. Clamp the graduated cylinder the ring stand of the lab table to keep it in place. perforate a hole in the top of the rubber cork for the solution container. Cut a straw the length of about four inches. place the straw inside of the rubber cork hole. Set up your timer for two minutes.
Diffusion and Osmosis Experiment with a Shell-Less Egg After Three days of Testing Methods with Water and Corn Syrup
Showing an example of diffusion with the water molecules equally back and forth the semi-permeable membrane of the potatoes and the saucer of water. The hypertonic solution of salt water has given an example of osmosis. The water molecules passed through the semi-permeable membrane out of the potatoes but weren’t able to get back in as easily due to the salt blocking the membranes passage. This left the potatoes in the salt water saucer feeling flexible and spongy almost leaving the potato a little
The following hypothesis was made in regard to effect of the concentration gradient on the rate of diffusion: The higher the concentration gradient, the faster the rate of diffusion.
The next experiment was to test diffusion in agar solution. A petri dish with a layer of solidified agar had four holes punched in it using a No. 5 cork borer. Three holes were punched in a triangle shape with the fourth hole directly in the middle. There should be 15 mm between each outside hole and the middle hole. The three outside holes were filled with one drop each of potassium bromide, potassium Terri cyanide, and sodium chloride. The middle hole was filled with a drop of silver nitrate. It is very important to make sure that none of the holes overflow. After each has been filled allow to sit for an hour and observe the results.
Diffusion is the spontaneous movement of particles from where they are more concentrated to where they are less concentrated. For this experiment, a 14 cm glass was filled with cold tap water. A drop of red food coloring was dropped in the cup. A stopwatch was used to measure the time it took for the food coloring to get to the bottom of the cup. The average diffusion rate was .78 cm a second. If a different color was used, I do not think it would have made a difference in the results. The mood of the person experimenting could possibly alter the results. For example, if a person is under stress, they may accidentally squeeze too much altering the rate of diffusion. If the water was warmer, this may have sped the
Diffusion is the passage of solute molecules from an area of high concentration to an area of low concentration (Campbell & Reece, 2005). An example is ammonia diffusing throughout a room. A solute is one of two components in a chemical solution. The solute is the substance dissolved in the solution. The solvent, the other component, is any liquid in which the solute can be dissolved (Anderson, 2002). Diffusion requires little or no energy because molecules are always randomly moving; this is due to their kinetic energy. Diffusion occurs only when there is an imbalance in the areas of
Add 3 drops of iodine solution * Shake it well,