Introduction: Certain species of fish are able to survive freezing temperatures in water by lowering the freezing point of water in their bodies by increasing the concentration of the dissolved solutes in their blood plasma and their tissues. Freezing point is a colligative property. The experiment provides students with experience to learn how to find the molecular weight of a solute by using their freezing point. Materials and Methods: The experiment began by gathering the materials. The materials consisted of a ring stand, test tube clamp, 600 mL beaker, 10 cm watch glass, Vernier temperature probe, alcohol thermometer, 11 dram vial, cork with a slit cut in side, spatula, powder funnel, rubber band, 20 cm wire, top-loading balance, analytical …show more content…
Unknown C was determined to be glucose with a percent error of 58.5%. If tap water was the solvent of the experiment, the results would look different. Tap water has impurities in the solvent. Therefore, it would take longer to freeze. The freezing point would be quite lower. In northern states, they use salt on the road to lower the freezing point of the road. They want to lower the freezing point so that salt does not form on the road. Thus, preventing car accidents from happening. Salt is a better solute than sucrose because salt has a lower molecular weight causing the freezing point depression to be higher. When the freezing point depression is higher, the freezing point of the solution will be lower. Conclusion: All in all, the freezing point was used to determine the molecular weight of the unknown solid. The experiment was successful except to one error in trail two. In trail two, the temperature never plateaued making the calculations for molecular weight not accurate. This caused the percent error to be high. Trail 3 was successful in determining glucose to be the unknown
If I had a chance to do this experiment once again. I would improve this experiment by actually testing, whether temperature affects the rate of reaction of the alka seltzer tablet, by having the water be hot, warm and cold, and determine at which temperate does the tablet dissolve faster. I could also change the amount of water I used during the experiment, as I only used 100ml of water in a 400ml beaker. I would also change the temperate of the room. A further investigation can study how temperature affects the rate of reaction between water and alka seltzer tablets.
As much was conducted throughout this lab, the projected completion of this lab displays that ultimately, the higher the temperature of the water, the faster the dissolving rate of the Alka-Seltzer is. In other words, the hotter the water temperature the quicker the tablet dissolves within the water in regards to the amount of time it took to dissolve. Furthermore, this experiment helps to explain that, if water is taken at a higher temperature and Alka-Seltzer is placed within the water, the Alka-Seltzer will take less time to dissolve because the higher temperatures cause the tablet to melt at a quicker rate. This compares to when Alka-Seltzer is placed in colder temperatures, where instead it takes more time to dissolve, because the lower
If dry ice is placed in Coca Cola, then it will sublimate the fastest because the carbonation bubbles that are in Coca Cola will scrape the sides of the piece of dry ice creating friction and heating it up the fastest. Table 1. Experimental Variables
Introduction The intent of this experiment is to understand how hot and cold water interact with each other by combining clear hot water and black ice cold water. I hope to learn more about how hot and cold water interact with each other. As of now, I know that cold water is denser than hot water. Knowing this I formed my hypothesis.
Experiment: EXP5-Percent of Water in Hydrated Salt Manika Srivastava Lab Partner: Natasha Seebaran Chem 1300/DA3 Date: 1/30/18 Professor Richard H. Perry Abstract: The purpose of this experiment was to determine the percent by mass of water in a hydrated salt as well as learn to handle a laboratory apparatus without touching it. The mass of water lost in grams for trials 1 and 2 are 1.7220g and 1. 2993g.
Exploration Title: Effect of Temperature on rate of Osmosis Submitted By: Abdulkarim Kamal Date Submitted: October 19th 2015 Subject: Biology HL Teacher: Mr. Nick Aim: This is an investigation to determine the relation between temperature of a solution (sucrose) and the rate of osmosis Scientific Context: Osmosis is defined a passive transport process in which a fluid diffuses across a semi-permeable membrane, from an area of high solute concentration to an area of low solute concentration and vice-versa. There are various factors that could potentially influence the rate of osmosis; these factors include volume, concentration, and temperature. If all external factors that may interfere with rate of osmosis are controlled, the results will show equal amounts of fluid on both sides of the barrier (membrane); this is known as an “isotonic” state.
The sample was frozen at -30 C to see the amount of caffeine was in it. Then the players
This is an important result as it shows that table salt helps ice cubes melt faster, which has application in real life situations such as snow or ice on roads and making ice cream. It would be useful to investigate this further by testing a greater range of substances and maybe combinations of substances onto the ice cube, to determine whether there are quicker ways to melt and ice cube. Explain any problems or issues encountered in carrying out your experiment. Acknowledgements I would like to acknowledge • Ms Roy for checking my proposal to see if my experiment was able to be done • My parents for providing me with the equipment for my experiment •
Vitamin C is sensitive to temperature (presence of heat), exposure to light and exposure to air (oxygen). It is considered ‘the most easily destroyed vitamin’. [4] Hypothesis: If the Vitamin C is to be frozen and thawed then the molecules will be destroyed, thus decreasing the concentration of the substance. According to the experiment, the main factor that will have to be taken into account of when freezing, will be the blanching process.
Sodium Chloride, is soluble in water, because it is polar and has an alternating negative anion and positive cation. Water is also polar, so like will dissolve in like. Therefore, the negative part of the chloride ions are attracted to the positive side of the water molecule and the negative side of the water molecules is attracted to the positive sodium atom. The negative oxygen charges in water, attract to the positive sodium ions in sodium chloride. Sucrose is soluble in water, because it is a polar molecule and the polar molecules in water attract the positive and negative regions around the sucrose molecules, which allows sucrose to be soluble in water.
In the beginning of the experiment, both planets would have around the same temperature; however, the thinner atmosphere would eventually be hotter, then subside toward the end of the experiment. Two beakers with differing thicknesses of plastic wrap, with a lamp overhead, represents this scenario. According to a group’s data (their group number to be determined), both beakers with differing atmospheres steadily increase by 1℃ respectively until the fifth minute, where the planet with the thinner atmosphere has a hotter surface temperature. After four more trials, the beaker with the thinner atmosphere would increase until both beakers are around the same temperature again. In another group’s data (their group number also inconclusive), both
One reason that could happen is because one researcher did not conduct the experiment correctly, so their data brought the average
For example, in the response experiment, a yeast solution was prepared without sugar mistakenly and thus had to be prepared again. This suggests that other errors in preparation and measurement could have been encountered. For the future, careful measurements using clean uncontaminated flasks would eliminate possibilities of such error. A source of error for the metabolism experiment involves the yeast’s yellow hue. It is possible that the color of the yeast caused the solution to look more
In this experiment, the amount of water lost in the 0.99 gram sample of hydrated salt was 0.35 grams, meaning that 35.4% of the salt’s mass was water. The unknown salt’s percent water is closest to that of Copper (II) Sulfate Pentahydrate, or CuSO4 ⋅ 5H2O. The percent error from the accepted percent water in CuSO4 ⋅ 5H2O is 1.67%, since the calculated value came out to be 0.6 less than the accepted value of 36.0%.This lab may have had some issues or sources of error, including the possibility of insufficient heating, meaning that some water may not have evaporated, that the scale was uncalibrated, or that the evaporating dish was still hot while being measured. This would have resulted in convection currents pushing up on the plate and making it seem lighter by lifting it up
The density of a substance is a physical constant at a given temperature. The density of water changes as temperature changes. Water is more dense at 4°C and 1 atmosphere of pressure and becomes less dense as it freezes. This property of water is important to life on earth. If water became denser as it froze, as most substances do, lakes would freeze from the bottom up and life in would die.