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Chemistry/Honors Chemistry B: Calorimetry and Specific Heat Lab – Unit 2 Lesson 4 (see end of worksheet for points breakdown)You can do this in classkick if you prefer: AJ5 6GK is the class codeYou work for a company that wants to make cookware. You want to know which metal- aluminum, iron, copper, or lead- is best to use to make pots and pans. The specific heat is a valuable piece of information. If a metal has a low specific heat, then the metal could make an excellent material for cookware because it takes less heat to raise the temperature of the metal to cook food.You will use a calorimeter to collect data that enables you to calculate the specific heat of all four metals. Then you will use this data and information about cost, density, and safety to determine which metal would make the best cookware.Question: How can you determine the specific heat of a metal using a calorimeter?Hypothesis: Of the metals, that you will test (aluminum, iron, copper, or lead), which one do you feel will have the lowest specific heat capacity? Remember, the lowest specific heat means that it will take less energy to raise the temperature of the metal to cook food.ANSWER: Virtual Lab – please find the lab through the actual lesson in Connexus – the links have not been working correctly. Step 2: Assemble a Coffee Cup CalorimeterFollowing the onscreen instructions, assemble the calorimeterStep 3: Measure the masses of the metalsFollowing the onscreen instructions, measure the masse of the metalsMake sure to tare, or ‘zero’ the balance after each measurementAluminumCopperIronLeadmmetals mass of metal (g)Step 4: Heat the metals to 100 degrees Celsius in a hot water bathFollow the onscreen instructions to heat the metalsClick next when they have finished heating. There is nothing to do after this step (for data)Step 5: Measure the mass of the waterThis will be done for each type of metal, so please use the chart under step 7Step 6: Reassemble the calorimeter and position the thermometerStep 7: Put the metals in the water and measure the temperature changes for each metal separatelyAluminumCopperIronLeadMass of calorimeter (no lid) (g)Mass of calorimeter (no lid) + water (g)Mwater mass of water (g) – subtract masses aboveInitial temperature of metal (*C)Initial temperature of water (*C)Final temperature of both (*C)?Twater(*C) (Final – initial) ?Tmetal(*C) (Final – Initial)Step 8: Compute the specific heat of each metalUsing the values that you found during this lab, compute the specific heat of each substance of each metal using the equation: SHOW WORK BELOW FOR AT LEAST TWO CALCULATIONS FOR POINTSAluminumCopperIronLeadSpecific heat of metal, cmetal(J/g*C)Considering only specific heat, which metal would be the most ideal for use in cookware? Why?ANSWER 1:Looking at the factors of specific heat, cost, density (which can indicate how heavy it is), and safety risks, which metal would be the most ideal for use in cookware? Why?AluminumCopperIronLeadCost of metal$1.00/pound$5.00/pound$0.10/pound$1.00/poundSafety RiskSlight: corrodes easily when exposed to acidic foodsSlight: toxic at high concentration; can leach from pansNone: Source of beneficial dietary ironSignificant: toxic when ingested, can leach from pansDensity of metal (g/cm^3)2.708.927.8711.3ANSWER 2: Honors Chemistry Only – show all work to get creditA 55.0-g piece of copper wire is heated, and the temperature of the wire changes from 19.0°C to 86.0°C. The amount of heat absorbed is 343 cal. What is the specific heat of copper? Show your pound A is burned in a bomb calorimeter that contains 2.50 liters of water. If the combustion of 0.175 moles of this compound causes the temperature of the water to rise 45.00 C, what is the molar heat of combustion of compound A? The heat capacity of water is 4.184 J / pound B is burned in a bomb calorimeter that contains 1.50 liters of water. When I burned 50.0 grams of compound B in the calorimeter, the temperature rise of the water in the calorimeter was 35.00 C. If the heat of combustion of compound B is 2,150 kJ/mol, what is the molar mass of compound B?The molar heat of combustion of compound C is 1,250 kJ/mol. If I were to burn 0.115 moles of this compound in a bomb calorimeter with a reservoir that holds 2.50 L of water, what would the expected temperature increase be?Grading ChemistryHypothesis: 10Mass table: 10Temperature change table: 25Specific heat calculations work: 10Specific heat table: 15Answer 1: 15Answer 2: 15?Grading Honors ChemistryHypothesis: 5Mass table: 10Temperature change table: 20Specific heat calculations work: 10Specific heat table: 15Answer 1: 10Answer 2: 10Honors Section: 20 ................
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