Lab Report Testing Reactions with a Calorimeter
A team was sent to the chemical manufacturing division of a small chemical company to help the technicians with experiments. Since the notes written by the technicians were inaccurate and unfinished, all of the experiments they had preformed needed to redone and documented correctly. The head of the company gave the new team the task of trying to figure out why some chemical reactions caused the reaction vessel to get cold and others caused the vessel to get hot. The group constructed ¡°an apparatus to measure the quantity of thermal energy gained or lost during the chemical reactions¡± (Bellama, 193). This device was called a calorimeter. A series of different reactions were conducted using two different calorimeters. First, hot and cold water tests were preformed. Based on these results the scientists calculated the heat capacities of the calorimeter. The density and specific heat of pure water were used for these calculations. The other tests that were redone and recalculated were: salts in water, precipitation reactions, and acid base reactions. Then the question of whether the solution absorbed or gave off heat can be answered. Also, whether or not the concentration of an acid base reaction made a difference in the heat absorbed or lost can then be resolved. The goal is to determine if the reactions gave off heat or became cold. The factors that affect heat energy changes were identified (Cooper, 103).
The results for the heat capacities of the calorimeters were determined using the hot and cold water tests. Data was gathered from this experiment and calculations were preformed that resulted in the figures shown in table 1.
Table 1 ¨C Heat Capacity of C...
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...eter Two. The initial temperature of the hydrochloric acid was recorded. Twenty milliliters of sodium hydroxide were measured into a graduated cylinder and added into the calorimeter. The temperature was immediately recorded. The solution was monitored, and the temperature was recorded every ten seconds until it began to decrease. The solution was properly disposed of. The above procedure was repeated two more times using 3 M and 6 M concentrations of hydrochloric acid and sodium hydroxide. All results were observed and recorded, and the solutions were properly disposed of. Equations in the lab manual were used to calculate the ∆H for each experiment.
Bibliography:
Bellama, Jon. General Chemistry: Third Edition. New York: Brooks/Cole Publishing Company,
1999.
Cooper, Melanie. Cooperative Chemistry. New York: McGraw-Hill, 1995. 60-62.
First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three
We began this investigation by suiting up in lab aprons and goggles, we then gathered our materials, found a lab station and got to work. We decided to start with the magnesium in hydrochloric acid first, we measured out 198.5 L of HCl and put it in the foam-cup calorimeter and took initial temperature reading. We then selected a piece of magnesium ribbon and found its mass: 0.01g. This piece was placed in the calorimeter and the lid was shut immediately to prevent heat from escaping. We “swirled” the liquid mixture in the calorimeter to ensure a reaction, and waited for a temperature change. After a few moments, the final temperature was recorded and DT determined.
By adding fresh cold water it should cool the copper calorimeter. By making sure I do these checks before I do the experiment means that I should be able to get accurate results as the test will have been run fairly and hopefully successfully as there should not have been anything gone wrong. To make sure all the measurements are correct, I will also run checks. These checks when recording the data are. Make sure to check the thermometer to see what temperature the water is at the start, so I am able to see what it has to be when its been heated by 10 degrees.
Specific heat capacity of aqueous solution (taken as water = 4.18 J.g-1.K-1). T = Temperature change (oK). We can thus determine the enthalpy changes of reaction 1 and reaction 2 using the mean (14) of the data obtained. Reaction 1: H = 50 x 4.18 x -2.12.
The porpoise of these is to determine the Specific Heat. Also known as Heat Capacity, the specific heat is the amount of the Heat Per Unit mass required to raise the temperature by one degree Celsius. The relationship between heat and temperature changed is usually expected in the form shown. The relationship does not apply if a phase change is encountered because the heat added or removed during a phase change does not change the temperature.
The objective of this experiment was to identify a metal based on its specific heat using calorimetry. The unknown metals specific heat was measured in two different settings, room temperature water and cold water. Using two different temperatures of water would prove that the specific heat remained constant. The heated metal was placed into the two different water temperatures during two separate trials, and then the measurements were recorded. Through the measurements taken and plugged into the equation, two specific heats were found. Taking the two specific heats and averaging them, it was then that
In this lab, I determined the amount of heat exchanged in four different chemical reactions only using two different compounds and water. The two compounds used were Magnesium Hydroxide and Citric Acid. Both compounds were in there solid states in powder form. Magnesium Hydroxide was mixed with water and the change in heat was measured using a thermometer. The next reaction combined citric acid and magnesium hydroxide in water. The change in heat was measured as well. For the third reaction citric acid was placed in water to measure the change in heat. In the last reaction, citric acid was combined with water. The heat exchanged was again measured. It is obvious we were studying the calorimetry of each reaction. We used a calorimeter
Input variables In this experiment there are two main factors that can affect the rate of the reaction. These key factors can change the rate of the reaction by either increasing it or decreasing it. These were considered and controlled so that they did not disrupt the success of the experiment. Temperature-
Calorimetry, derived from the Latin calor meaning heat, and the Greek metry meaning to measure, is the science of measuring the amount of heat. All calorimetric techniques are therefore based on the measurement of heat that may be generated, consumed or simply dissipated by a sample. Calorimetry is used to find out how much heat is released or how much energy is absorbed, this helps determine if a chemical reaction is a endothermic or an exothermic reaction. Calorimetry is applied in the body, used to maintain metabolism in the body and body temperature itself.
In a 100ml beaker 30mls of water was placed the temperature of the water was recorded. 1 teaspoon of Ammonium Nitrate was added to the water and stirred until dissolved. The temperature was then recorded again. This was to see the difference between the initial temperature and the final temperature.
This is expressed as Δ +ve (delta positive). If the total energy put in is less than the energy created, then the substance warms up (it is exothermic). This is expressed as Δ -ve (delta negative). I will investigate eight different alcohols using an alcohol or spirit burner, to measure the energy change during burning by measuring the change in temperature of some water held in a container.
The Effect of Temperature of Hydrochloric Acid on the Rate of Reaction Between Hydrochloric Acid and Magnesium
Effect of Temperature on the Rate of Reaction between Sodium Thiosulphate and Hydrochloric Acid Investigation Chemical reactions are used in our everyday life, they literally keep us alive. They are used in food, respiration and everywhere else in the environment. A chemical reaction mainly occurs when reactants react together to produce a new product. The speed at which this reaction takes place is called the rate of reaction. The product produced has a number of particles in the solution that has formed from the reactants.
Conclusion This experiment was set out to find the effect of different temperatures of hydrochloric acid on the rate of reaction with magnesium. The information recorded was then interpreted and compared to the hypothesis. From this information, a conclusion can be made to show that the rate of reaction relates to temperature in the reaction between hydrochloric acid and magnesium. In conclusion, as proven in this experiment, the higher the temperature of hydrochloric acid, the faster the reaction it has with magnesium.
Methodology: A plastic cup was filled half way with crushed ice and mixed with four spoonfuls of 5 mL of sodium chloride. A thermometer was quickly placed inside the cup to take the temperature and the