Matthew Knutson Andrew Ford, Julia Hong 2/12/2015 Period 3 Specific Heat of a Metal Lab Report Introduction: The purpose of this lab was to identify the type of metal and its specific heat capacity that was used to conduct the experiment. It was also performed to visualize the flow of heat phenomenon, and to apply the principal of conservation of thermal energy. All four goals were accomplished upon completion of this experiment. This lab was based around the idea of heat. For the purpose of this experiment we described heat as the transfer of energy between two objects and used temperature as a way to record and quantify the amount of heat that was transferred. We used the concept of thermal equilibrium in order to calculate the heat energy that was gained by the water and the specific heat of the metal as well. Thermal equilibrium states that two objects that are in contact and start at two different temperatures will eventually reach the same temperature. This was described by the equation Qmetal = Qwater. We also used the specific heat which is the amount of heat energy that is required to raise one gram of a substance one degree Celsius in order to compare to current graphs and reveal the identity of the metal we were experimenting with. We used two units in order to calculate our data. The first being Joule (J) which is the metric unit for heat energy, and the second being calories “cal” which is the amount of energy/heat required to increase the temperature of one gram of water by one degree Celsius. We first arrived in class and put on the necessary safety equipment and began setting up our lab station. We used a stand to hold a beaker full of water above a Bunsen burner with a test tube containing pennies held slightly in the water by a clamp on the stand. Once this was set up we lit the Bunsen burner and waited for the water to start boiling. While waiting we poured room temperature water into a foam cup that was inside of another beaker for support. Once it was observed that the water was boiling we let the metal sit in the hot water for 10 min and took the temperature of the hot water, the metal, and the room temperature water. We then poured the pennies into the foam cup and measured the final temperature once it stopped fluctuating. We used this data to calculate the heat energy gained by the water and the specific heat of the metal. It was hypothesized that the metal we were working with was Copper (CU). We came to this hypothesis by visual observations of the color and texture of the metal samples which happened to be pennies. Procedure: Materials: - Stand (1) - Clamp (1) - 250-mL Beaker (1) - Graduated Cylinder (1) - Thermometer (2) - Water - Bunsen Burner (1) - Pennies - Test Tube (1) - Foam Cup (1) Procedure: 1- Filled a 250-Ml Beaker ¾ full of water. Placed the beaker on the stand above the Bunsen burner. Used the Bunsen burner to bring the water to a slow boil. 2- Obtained a small sample of the metal being used that will fill the test tube about ¼ full. Found the mass of the metal to the nearest 0.01 g and recorded on the table. 3- Transferred the metal to a dry test tube. Suspended the tube in the boiling water using the clamp. Allowed the test tube to remain in the boiling water for 10 min. 4- Measured 100 Ml of water in a graduated cylinder and poured it into a foam cup placed inside of a beaker. Placed a thermometer inside. 5- Let heat for 10 min then measured the temp of hot water with thermometer and recorded. Recorded temp of cool water and recorded on table as initial temp of metal and water in calorimeter. 6- Removed test tube from boiling water and poured metal sample into foam cup. Stirred sample. Record max temperature of water as final temperature of water and metal. 7- Calculated changes in temp of water and metal as well as heat energy gained by water and specific heat of metal. Recorded all calculations in table. Data: Data Table Metal Sample Mass of water in Calorimeter mwater Mass of the metal sample mmetal Initial temp of metal sample Initial temp of water in calorimeter Final temp of water and metal g G ºC ºC ºC 1 100 56.9 95 22 26

Calculations Table Metal sample Change of temp of water Change of temp of Metal Heat energy gained by the water Specific Heat of the metal Error ºC ºC cal Cal/g.ºC % 1 4 -69 791.88 .102 9.6

Analysis: This data shows that the specific heat of the metal that was used was .102 Cal/g.ºC with an error margin of 9.6%. Discussion: With the data that we observed and recorded it was concluded that the un-known metal sample that was used in this experiment was copper. This was concluded by comparing our calculated specific heat of the metal to the list of metals provided on the first page of the lab. This included AI as 0.215, Lead as 0.031, CU as 0.093 Cal/g.ºC, and Iron as 0.113. When our number of .102 Cal/g.ºC was compared to this chart it was concluded that the identity of the metal was CU which was off by 0.009 Cal/g.ºC. Our hypothesis that the mystery metal was copper was correct because our calculated specific heat of metal matched the universal specific heat of copper. The main area that could have created error in our experiment was the loss of heat energy to other substances during the multiple transfers that took place during the experiment. The first transfer where heat energy could have been lost was when the heat energy in the boiling water could have been lost to the air which was much cooler at room temperature. The second transfer that could’ve had a loss of heat energy would be when the metal was transferred from the boiling water and into the foam cup. Heat energy could’ve been released into the air in the time the test tube was being transferred from the boiling water to the calorimeter. Finally, even though we used the best insulator that we had available for the calorimeter which was foam; some heat energy was still transferred from the metal sample to the Styrofoam cup which may have caused an error in the recorded temperature change of the water. Further experiments on this topic could be done to more accurately calculate the specific heat of copper. This could be done by creating a more stable environment by using better insulators that don’t take in heat to prevent loss of heat energy during the testing. More accurate electronic thermometers should be used in order to produce more accurate data. Conclusion: It can be concluded that the mystery metal we experimented with was copper. It can also be concluded that the specific heat of any metal can be calculated using change in temperature and heat energy transferred. I learned that each metal has its own specific heat which is the amount of heat energy that is needed to raise the temperature of one gram of a substance by one degree Celsius. This concept can be used in order to identify metals that can’t be identified through its basic properties. Abstract: In this experiment we heated a metal sample and put in in room temperature water and recorded the change in temperature of both samples. We used data that was recorded during this experiment to calculate the heat energy that was gained by the water and then used this information to calculate the specific heat of the metal. Once this number was determined we compared it to the chart of universal specific heats of metals and found that our number of specific heat was the closest to coppers universal specific and then concluded that the mystery metal that we were working with was in fact copper. Questions: 1- It would increase 2- It would decrease 3-