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1、Specific Heat LabPurpose: To determine the unknown metal by calculating its specific heat.Procedure:1. Obtain a beaker and fill to 2/3 full of water. Get the water boiling!2. Record the mass of the metal.3. Place it in the heating water. (Make sure the metal is covered in water.) Heat until boiling
2、and then boil 5 minutes longer.4. Fill the sytrofoam cup about way full of water and find its mass. Record!5. Measure the temperature of the water in the styrofoam cup. Record (initial temp)6. After the water has boiled for five minutes, measure the temperature of the boiling water. 7. Remove the pi
3、ece of metal from the boiling water using tongs and place into the styrofoam cup. Record the temperature of the water every 30 seconds until the temperature remains constant for two consecutive readings.Final Water temperature (C)(after you add the metal)Time (min)Trial 1Trial 2Trial 30.00.51.01.52.
4、02.53.03.5Data TablesTrial 1Trial 2Trial 3Mass of metalMass of cupMass of cup+waterMass of waterInitial Temp MetalInitial Temp H2ODrawing: Draw a picture of the Styrofoam cup set-up. Draw arrows to show how heat is being transferred.Calculations:Use the equation Q=mcT and your drawing to determine t
5、he specific heat of the metal for trials 1,2 and 3. Hint: Make 2 columns (1 for what you know about the water and 1 for what you know about the metal) Questions: Answer in complete sentences.1. Compare your calculations to the specific heat of metals below. What do you think is the unknown metal? Ex
6、plain your reasoning.Aluminum = 0.900 J/gCIron = 0.444 J/gCLead = 0.130 J/gCZinc = 0.39 J/gCNickel = 0.54 J/gCCopper = 0.385 J/gCBrass = 0.377 J/gC2. Which component (the metal or water) experienced a greater change in temperature (T)?3. Give one possible explanation for your observations in questio
7、n #2:4. Use percent error formula to show error. (actual-experimental)/actual)x 100)5. Consider each of the following potential sources of errors:Answer “H” if it would have caused your experimental value for the metal to come out too high, “L” if it would have caused it to come out too low, or “N”
8、if it would have had no effect at all on your value._ You forgot to subtract the mass of the empty cup_ You used a metal can (which conducts heat away) instead of Styrofoam (which insulates)_ You drank some of your calorimeter water after you found its mass_ After weighing the metal, a chunk of it b
9、roke off and was lost on the floor._ You used a Styrofoam lid to contain the heat in the cup_ The heat from the metal heated up the water to boilingThese Problems are HOT, HOT, HOTSubstance Specific Heat (J/goC) Liquid Water 4.184or 1 cal/ goCSolid Water2.14Gaseous Water2.01 For water: Heat of fusio
10、n: 334 J/g andHeat of vaporization: 2260 J/g1. What quantity of heat is necessary to raise the temp. of 5.00 grams of ice from -15.0 oC to 117 oC? A: 15400 J2. How much heat, in calories, is required to change a 15 gram piece of ice at -20 oC to water at 5 oC? A: 1400 cal3. What quantity of heat is
11、needed to change 50 g of water from 25 oC completely to steam? A: 129000J4. A piece of metal at 100 oC is placed in 75 grams of water at 25 oC. The water temp. raises to 30 oC. Assuming that the C of the metal is 0.2 cal/g oC, what is the mass of the metal? (heat gained = heat lost) A: 26.7 g5. How
12、much heat is required to heat a one liter bottle of water from 25 oC to 100 oC? The density of water is 1 g/ml. A: 3.1x105J6. To what temperature could the energy inside a Snickers bars (250,000 calories) raise a 500 ml bottle of water? Assume the water starts at 25 oC. A: 525 oC7. What mass of ice
13、would be necessary to cool a 500.0 ml glass of water from 25 oC to 5 oC? (heat gained=heat lost) A: 3900 gThese Problems are HOT, HOT, HOTSubstance Specific Heat (J/goC) Liquid Water 4.184or 1 cal/ goCSolid Water2.14Gaseous Water2.01 For water: Heat of fusion: 334 J/g andHeat of vaporization: 2260 J
14、/g1. What quantity of heat is necessary to raise the temp. of 5.00 grams of ice from -15.0 oC to 117 oC? A: 15400 J2. How much heat, in calories, is required to change a 15 gram piece of ice at -20 oC to water at 5 oC? A: 1400 cal3. What quantity of heat is needed to change 50 g of water from 25 oC
15、completely to steam? A: 129000J4. A piece of metal at 100 oC is placed in 75 grams of water at 25 oC. The water temp. raises to 30 oC. Assuming that the C of the metal is 0.2 cal/g oC, what is the mass of the metal? (heat gained = heat lost) A: 26.7 g5. How much heat is required to heat a one liter bottle of water from 25 oC to 100 oC? The density of water i
