Agar Jelly Experiment Report

AimTo find out the speed of diffusion in agar jelly, when there are three blocks of jelly of different sizes. heartyA container with agar jelly, safety goggle, lingua, ruler, separate watch, a glass plate, sodium hydrated oxide, an indicator.MethodFirst, we took the block of agar jelly from the container. We placed it onto the glass plate, and took our knife and ruler. We measured and cut the block, making three stops of different measurements. The smallest one is 1cm by 1cm by 1cm, the second one is 2cm by 2cm by 2cm, and the biggest one is 3cm by 3cm by 3cm. We then dropped a few drops of the indicator. Next, we put our safety gape on, and took the beaker full of sodium hydroxide, and poured it into the glass plate, which the cubes are in.At the same time, we started the stop watch. We aphorism everything, the cubes, sodium hydroxide turn pink (thats because sodium hydroxide reacted with the indicator). When the stop watch showed 5 spots, we took the cubes, and cut all of t hem in half. hence we measured the outmatch from the surface, to the line where the pink and the white gloss separate, equivalent on the diagram, using our ruler. We recorded what we saw, and the results.ResultsWe saw the cubes turn pink, and the sodium hydroxide turn pink on the plate. We also saw, when we cut the cubes that the pink colourize travelled into the cube, and we saw that at a certain point, there was the time interval of pink from the surface, to white, the color of agar jelly. Like I said, we measured the distance between the surface to where the separation line of pink and white color was. This is what we got1cm*1cm*1cm 4mm2cm*2cm*2cm 4mm3cm*3cm*3cm 4mmAlthough they were all 4mm, we saw that the smallest cube was al more or less completely diffused, almost everything was pink. And we saw that the biggest cube was not at all completely diffused most of it was white inside the cube.Speed of Diffusion=Distance/Time4mm/5minutes=0.8mm/minuteConclusionsFrom this expe riment, I learned these thingsFirstly, I learned that the pink color travelled into the cube, because of diffusion. Diffusion is when particles move from an area of high concentration to an area of embarrassed concentration. So in this experiment, the sodium hydroxide diffused from the high intemperate area (which is the surface of the cube, as sodium hydroxide was poured onto the cube) to low saturated area (inside the cube). I also learned that even if you change the volume, or the surface area of the agar jelly, the speed in diffusion doesnt change. As you can see from the results, no matter the size of the cube, the sodium hydroxide diffused at the same speed. The speed of diffusion can be calculated by distance/time. In this experiment, we saw that the distance which the sodium hydroxide traveled was 4mm, and the time we used was 5 minutes. So, 4mm/5min= 0.8mm/minute.Because the speed doesnt change, the little the cube, the faster itll get completely diffused.From this expe riment, I can expect that 1cm*1cm*1cm cube jelly give be completely diffused in 6minutes 15seconds, because 1cm/0.8mm*2=6.25min. (times 2 because it diffused from the top and the bottom). In the same way, I calculated that 2cm*2cm*2cm cubed jelly will be completely diffused in 12.5minutes and 3cm*3cm*3cm jelly in 18.75minutes. You can see that 2cm*2cm*2cm jelly will take twice as much time as 1cm cubed one and 3cm*3cm*3cm jelly will take three times as much time as the 1cm cubed block.