Aaron+and+Stephanie-+Calorimetry+Lab

=Calorimetry=
 * Participants** : Aaron Locke, Stephanie Morse
 * Purpose** : The purpose of this lab is to identify an unknown metal by its specific heat.

The calorimeter used in this experiment had quite a simple set up. It was made up of two aluminum containers, with one smaller one placed inside the larger one. The small container sat on a plastic ring that created a flush seal with the suspension ring. This removable piece allowed for air to be trapped inside. The trapped air between the two containers insulated the inside container, so that no outside forces could effect it. A black lid covered the entire set up. It had two holes. One was used to hold the thermometer and another held a stirring rod.
 * Brief Description of Calorimeter:**

Like previous labs, this lab forced you to discover the procedure for finding the specific heat of an unknown metal by yourself. We were given the materials necessary and it was up to us to find out how to use them correctly to achieve the goal. We used a calorimeter, that looked like a can within a can. There was a large can that was left empty, and a smaller can that rested inside. The metal we used was kept in a pot of boiling water while it was not in use. We would test the specific heat by putting the hot metal into the small container in the calorimeter, and then measuring it's temperature. See below for complete procedure.
 * Brief Description of Experiment** :

1. Fill the small section of the calorimeter with room temperature water and then measure the mass. 2. Place the cup back into the calorimeter and seal the top. 3. Begin measuring the temperature with LoggerPro. 4. Quickly take a piece of metal from the boiling water and place it in the calorimeter. Try to avoid heat loss and dropping the metal. 5. Continue measuring the temperature using LoggerPro. 6. When the temperature tops off, remove the metal and measure it's mass. 7. Replace the metal into the boiling water, empty the calorimeter, save the graph on LoggerPro. 8. Record the mass and temperature of the metal and water. 9. Record the final temperature, the change in temperature of both the water and the metal. 10. Repeat above steps three times.
 * Procedure:**


 * Data** :

(g) ||= Temp. Metal (C) ||= Mass Water (g) ||= Temp. Water (C) ||= Final Temp. (C) ||= Change In Temp. (Water) ||= Change In Temp. (Metal) ||
 * =  ||= Mass Metal
 * = Trial One​ ||= 112.67 ||= 100 ||= 299.04 ||= 23.4 ||= 26.0 ||= 2.6 ||= 74 ||
 * = Trial Two ||= 113.42 ||= 100 ||= 289.2 ||= 25.4 ||= 27.9 ||= 2.5 ||= 72.1 ||
 * = Trial Three ||= 110.29 ||= 100 ||= 278.24 ||= 24.9 ||= 27.8 ||= 2.9 ||= 72.2 ||
 * = Trial Four ||= 112.50 ||= 100 ||= 277.05 ||= 24.7 ||= 27.2 ||= 2.5 ||= 72.8 ||

Trial One: Trial Two: Trial Three Trial Four:
 * Sample Calculations:**
 * //Specific Heat// || Once you have collected all the necessary data, use the specific heat equation to determine the specific heat of the unknown metal.

C = Q / m x (delta)T ||
 * Calculations:

Finding the specific heat constant for the metal:

C =** (4.186) / (112.67 x 2.6) = 4.186 / 292.942 = .014

C = (4.186) / (113.42 x 2.5) = 4.186 / 283.55 = .014

C = (4.

The results of this lab were pretty straight forward. Our numbers consistently in the same ballpark, and so did our specific heats. Our graphs all reflected the same type of increase in heat and correspond with each other nicely. Before we started the lab, we were already aware that specific heat is the amount of heat required to raise the temperature one degree celcius. The lab helped to further enforce this knowledge and really put it into action. We now visually can see the process that is used to change the temperature and how it relates to specific heat. We faced problems such as heat loss before the metal even reaches the calorimeter, but those type of inaccuracies were kept consistent so they did not have an effect upon the lab. Through finding the average specific heat, we have concluded that our metal is Selenium, a metal with a .32 specific heat.


 * Lab Questions** :

1. In what ways did you attempt to make your result as accurate as possible? Describe how each way contributed to a more accurate result.

//We faced the challenge of having the boiling water with the metal being far away from the calorimeter. To attempt to solve this problem, we moved the calorimeter as close as possible to the metal station, while it could still be measured, and had the top of the calorimeter off when the metal was dropped in. We then would seal the top as quickly as possible. Basically, we tried to make the process as fluid as possible to avoid any heat loss. Furthermore, we faced the problem of not using the same piece of metal continuously and having the metal not be at 100 C every time. To avoid this problem, we tried to put pieces of metal that had just been used on one side of the pot and ones that had on the other. We then kept a rotating cycle. It seemed to work because none of our data is extremely out in left field.//

2. In what ways does the calorimeter fail as a closed system? What mathematical effect on your result would these failures have?

//The calorimeter fails as a closed system for one reason. The cover must be taken off for the metal to go inside. If it was an actual closed system, the threat of escaping heat would not be so immenent. We attempted to solve this problem by only having the cover off when we desperately needed it. This effect would change the change in water temperature. Which would result in the specific heatbeing skewed.//

3. Suppose you were asked to measure the latent heat of vaporization of water (the amount of heat required to turn liquird water into a gas). You propose to do this by heating a bar of the mtal used in this experiment to a very high temperature (500 C) and dropping it into a calorimeter with water initially at 95 C. Describe what you think will happen and what measurments you would need to make in order to calculate the latent heat. Approximate how much water would be turned to steap if the bar had a mass of 0.7kg and the final temperature of the .35kg of water in the calorimeter was 100 C.

//Since heat transfers from objects with higher temperatures to objects with lowere temperatures, the 95 degree Celcius water would be heated by the 500 degree Celcius metal bar. By doing so at a certain temperature the water will change from a liquid to a gas, this is water's latent heat. In order to do this it would be neccessary to measure the initial mass of the water, the mass of the metal bar and the water's temperature throughout the entire experiment.//


 * Conclusion** : A good conclusion will include:
 * A statement about whether you think that the experiment produced a valid and reproducible result and reasoning supporting your statement.
 * A suggestion as to why your experimental results differ from any accepted value or your expected result (if appropriate).
 * A suggestion for a simple improvement to the experiment. Think about what caused problems, measurement inaccuracies, or inappropriate simplifying assumptions and propose a change. A sketch may be helpful.

//Don't forget to link to your lab report from the lab reports page and to include a link to your lab report in your reflection.//