Our objective was to pick the best chemical to be used in a hand warm. This chemical had to be cheap, relatively safe, and must raise the temperature by 20oC and no more. We add 6 different chemicals to water we record the inshell temperature and then add one a the 6 chemicals to the water and record the temperature change of the water. We also add cold water hot water together to find how much heat would escape the calorimeter. We found that the calorimeter absorbed 71.1J/oC. Then this information to calculate the energy that was released by all of the chemical reaction. We found that Joules from NaCl = 340 J, NH4NO3 = 1340 J, CaCl2 = -2320 J, LiCl = -3600, Na2Cl3 = -720 J, NaC2H3O2= 1070 J. Then we used energy release from one one these rxn to calculate the Hor the KJ per mol rxn. …show more content…
After seeing this data the two most effective look chemical at resisting energy was CaCl2 and LiCl. So we looked at the price of both of this chemical CaCl2 cost 6.55$ per 500g and LiCl cost 32.75$ per 500g because CaCl2 was substantially cheaper we decide to chose it to use in own hand warmer. We calculated that it would take 22g of CaCl2 to create a 20oC increase in temperature of 100ml of water. Some sources of error in this lab, would be heat escape from not be able to replace the lid of the calorement went adding chemical into it, inaccuracies in the balance, and not waiting of the proper time to recode the
One way we could improve the experiment is by doing more trials, the more trials the more accurate the resolutes are. Another way we could improve the experiment is to have more time so we could make sure all the temperatures
The temperature probe was then quickly cooled to room temperature. When this was achieved, the hot water was immediately transferred into the calorimeter. This method of keeping the temperature probe cooled before measuring a new temperature was repeated throughout the entire experiment. Temperature data was collected for 180 s while swirling the temperature inside the calorimeter. The calorimeter still contained the warm water.
Experiment 1: Materials: • Alka-Seltzer tablets • Empty and clean water or soda bottles (12 oz to 24 oz) • Balloons • Water • Clock • Stove top Procedure: 1. Pour a sufficient amount of water (about 16 oz) into a small pot and place on the stove at high heat. 2. Watch the clock and after 30 seconds take the water off the heat.
The molar heat of combustion of a compound is 1250 kJ/mole. If 0.115 moles of this compound in a bomb calorimeter with 2.50 L of water, what would the temperature increase be? If change in heat is positive it is an _______ reaction If change in heat is negative it is an_______ reaction
Shifa Sayeed can you check if this is all in past tense and if it has personal pronouns? The purpose of this experiment was to observe and thoroughly analyze how different substances of dissimilar intermolecular forces acted in different scenarios of evaporation, evaporative cooling, and boiling. In the lab, the three substances tested and compared were Acetone, Acetic Acid, and Propanol.
Determination of the Heat Exchanged in Chemical Reactions Introduction: Calorimetry is the science of determining heat and energy exchange in various situations and reactions. It is used for many things everyday including solid and liquid fuel testing, waste disposal, and explosive testing. In our lab, we will are applying calorimetry to determine the change in enthalpy of a weak acid-strong base reaction. My beginning question was: How can we apply Hess’ law and calorimetry to chemical equations to determine the heat exchanged in a reaction?
The lab started off by measuring critical materials for the lab: the mass of an an empty 100 mL beaker, mass of beaker and copper chloride together(52.30 g), and the mass of three iron nails(2.73 g). The goal of this experiment is to determine the number of moles of copper and iron that would be produced in the reaction of iron and copper(II) chloride, the ratio of moles of iron to moles of copper, and the percent yield of copper produced. 2.00 grams of copper(II) chloride was added in the beaker to mix with 15 mL of distilled water. Then, three dry nails are placed in the copper(II) chloride solution for approximately 25 minutes. The three nails have to be scraped clean by sandpaper to make the surface of the nail shiny; if the nails are not clean, then some unknown substances might accidentally mix into the reaction and cause variations of the result.
They tested how the temperature would affect the rate of reaction. This was observed by the amount of time it took for the solution to change colors. For many chemical reactions there is an optimum temperature at which the chemicals will react with each other. As was found in their experiment, the temperature affected the rate of reaction. (Deoudes, 2010).
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.
Materials: The materials that I will be utilizing during these experimentations are three to four ice cubes, one cup for measuring, six unblemished cups, one stopwatch, one hot water source, three tablets of Alka-Seltzer, one thermometer that measures from negative
Elijah Brycth B. Jarlos IX-Argon 1. Multicellularity is a condition of an organism to have multicellular cells. An example of a organism who has multicellular cells are plants, animals, and humans. The main reason of why scientists have a hard time finding a good set of existing organisms to compare. Is neither the first set of organisms which is being compared is dying as fast as the second specimen is being examined or they just can’t find the right species.
Then the scientist will observe the different rates of reaction with temperature. The Boltzmann distribution of law, indicates that high temperature makes molecules gain high energy contents (pubs.acs.org/doi/abs/10.1021/ja). In order to measure the reaction rate, the scientists must use the same volume of water at three different starting temperatures: hot tap
In the warmth exchangers there are normally no outer responses to warmth and work. Down to earth applications incorporate worries about warming or cooling fluid vanishing or buildup of one or different liquid streams. In different applications, the objective may be reestablished or expel warmth or sanitization, purification and division, refining, fixation, crystallization, or control of the procedure liquid. In a few gadgets, and liquids that trade heat in direct contact. The vast majority of the warmth exchanger, and method for warmth exchange between the divider and Bond or transient way.
Another way to calculate the enthalpy of neutralization is to assume the density of the solution to be equal to the density of water in order to assume the mass of the solution. 1.00 g 〖cm〗^(-3)×50 cm^3±0.96 %= 50.00 g ±0.96 % The heat released can then be calculated using the assumed mass. q=50.00 g±0.96 % ×4.18 J g^(-1)
Consequently, it was discovered that the aluminium can with cotton wool that acted as an insulator was discovered to be the best material as the final result was 69.5°C.7 This differed to the aluminium can without material as an insulator with a temperature of 62°C at nine minutes. The can with aluminium foil started off with a temperature of 73.5°C and slowly made it’s way to 65°C, proceeded it to be the second best insulator despite the material to have worked better at being a conductor. The can that had no materials was discovered to be the least efficient at trapping heat energy from hot water because one layer will not make a big difference as because aluminium is known to conduct heat better than insulating thermal