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Characteristics of Matter #1 6. A 100 grams piece of metal increases its temperature from 20ºC to 60ºC when 2500 Joules of energy are added to it. What is the specific 1. How much energy is required to increase the temperature of 150 heat capacity of this metal? grams of water from 20ºC to 90ºC? 2. What is the mass of an iron skillet if its temperature increases 7. What is the mass of an aluminum pan if it requires 2000 Joules of 250ºC when 15000 J of energy is added to it? energy to increase its temperature 20ºC? 3. How much will the temperature of a 75 g silver fork increase if 2000 8. How much energy is given off by a 1500g iron pot as it cools from J of energy are added to it? 320ºC to 25ºC? 4. If the initial temperature of the fork in the preceding problem is 9. A cup of tea can be consumed without burning one's tongue when its 28ºC, what is the new temperature after it has been heated? temperature is 80ºC. Assuming that the specific heat of tea is basically the same as the water from which it is made, how much energy is absorbed by the body of the person who drinks a 125 g cup of tea as it cools in his stomach to a body temperature of 37ºC? 5. A child with the body temperature of 98ºC picks up a 20 g piece of aluminum at room temperature (25ºC). He puts this piece of aluminum in his pocket and eventually it warms up to his body temperature. How much energy did his body lose by warming this piece of aluminum? Characteristics of Matter #2 5. The density of turpentine is 0.868 g/ml. What is the mass of 250. 1. An object with a mass of 50.00 grams and volume of 100 mls is placed mls? in water. What is the density of this object? If the density of water is 1.00 g/cm3, will this object float? Matter Vocab Place the following in one of four categories: mixture, solution, pure element, pure compound. Table sugar:________________________ 2. A cube has a mass of 2.4 kg. Its dimensions are 4cm x 4cm x 4cm. What is its density? Water: ________________________ Coca-cola in a can: ________________________ Vegetable soup: ________________________ A penny: ________________________ 3. An object of unknown volume and a mass of 25.0 g is placed in a graduated cylinder filled with 3.5 mls of water. The water level in the Oxygen: ________________________ graduated cylinder rises to 21.5 mls when the object is completely submerged. What is the volume of the object? What is the density of Air: ________________________ the object? Will the object float? Salt water: ________________________ Sea water: ________________________ Helium: ________________________ 4. Mercury has a density of 13.6 g/cm3. If I need 25.0 grams of Of the following, circle those that are chemical changes and underline mercury, how many milliliters should I pour? those that are physical changes. melting butter baking brownies boiling water freezing alcohol popping popcorn melting steel shaking Sprite mixing vinegar/baking soda to generate bubbles Characteristics of Matter Practice Test 6. What is the volume of a piece of aluminum if it has a mass of 125 grams? 1. How much energy is required to increase the temperature of a 250 g iron pot from 28ºC to 190ºC? 7. How much energy is required to heat 200 g water from room temperature (25ºC) to boiling (100ºC)? 2. What is the mass of an copper skillet if its temperature increases 150ºC when 12000 J of energy are added to it? 8. List 5 physical characteristic of matter. 9. List 3 chemical characteristics of matter. 3. 3000 J of energy are added to a 135 g silver spoon. If the original temperature of the spoon is 26ºC, what is the new temperature of the spoon after the energy is added? 10. List four examples of a physical change. 4. When 878 J of energy are added to a 125 g piece of metal, the 11. List four examples of a chemical change. temperature of the metal increases from 22ºC to 40ºC. What is the specific heat of this metal? What is the identity of this metal? Densities of Common Metals Common Specific Heat Capacities Aluminum 2.71 g/cm3 Aluminum .91 J/gC Brass 8.5 g/cm3 Brass .377 J/gC Gold 19.3 g/cm3 Copper .39 J/gC 5. What is the density of a piece of metal if it has a mass of 28.0 grams Iron 7.85 g/cm3 Iron .46 J/gC and a volume of 3.18 mL? What is this metal? Nickel 8.8 g/cm3 Nickel .54 J/gC Platinum 21.4 g/cm3 Tin .21 J/gC Silver 10.5 g/cm3 Silver .24 J/gC Tin 7.28 g/cm3 Water 4.184 J/gC Titanium 4.5 g/cm3 o HONORS Lab 1: Specific Heat Capacity and Density Assume specific heat capacity of water to be 4.184J/g C. Assume all the heat lost by the hot metal is transferred to the cold water. of an Unknown Metal Assume the accepted value of specific heat capacity of iron to be 0.45J/g C. o Assume the accepted value of specific heat capacity of copper to be Purpose To calculate the specific heat capacity and density of a metal and o 0.385J/g C. to use this information to identify the metal. Assume the accepted value of specific heat capacity of aluminum to be o 0.89J/g C. Apparatus 250mL beaker, 2 coffee cups, 100mL measuring cylinder, hot plate, tongs, 2 thermometers, balance Data Tables Chemicals Water, sample of metal TABLE A Procedure Mass of metal sample Initial temperature of water in coffee 1. Place the metal sample on the balance and record the mass in table A. cup calorimeter 2. Using the measuring cylinder add exactly 120mL of water to a “double Temperature of hot water (metal) coffee cup calorimeter”. Using a thermometer record the temperature of the Initial volume of water in graduated water in table A and in table B. Set it aside. cylinder Final volume of water in graduated 3. Fill a 250mL beaker approximately half full with water and place it on the cylinder with metal cylinder submerged hot plate. Carefully add the metal sample. Adjust the hot plate to a medium- high heat setting. Using another thermometer, monitor the temperature of the Water temperature in coffee cup calorimeter water as it heats up and continue heating until the water temperature reaches approximately 90 C. o Time in seconds Temperature 0 o 4. When the water reaches approximately 90 C, turn off the hot plate and 30 remove the beaker. 60 90 5. Using tongs, carefully transfer the metal sample from the hot water to the 120 “double coffee cup calorimeter”. At this point record the temperature of the 150 hot water in table A. 180 210 6. Slowly sir the contents of the “double coffee cup calorimeter”, recording 240 the temperature every 30 seconds in table B. Continue to record the 270 temperature until a maximum temperature has been reached. 300 330 7. Dry the piece of metal. Obtain a 100 ml graduated cylinder. Place about 360 30 mls of water in the graduated cylinder and record the exact volume to 0.1 mL in the data table. Carefully and slowly drop the metal into the cylinder and record the new volume to 0.1 mL in the data table. Empty the graduated cylinder and return the metal to the prep table. Assumptions Assume the temperature of the sample of metal is the same as the hot water. Assume the density of water to be 1g/mL. Conclusion/Calculation (Complete this after you have finished the lab.) 1. Using the following relationships calculate the specific heat capacity of the metal and compare your result to the accepted value. Heat gained by wate r= (mass of water) x (cp of water) x (temp change of water) Heat lost from metal = (mass of metal) x (cp of metal) x (temp change of metal) 2. Calculate the density of the metal. d = m/v Remember that you can determine the volume of the cylinder by the displacement of water in the graduated cylinder (final volume - initial volume). 3. Identify two possible errors in your experiment. 4. Using a table of common densities and a table of common specific heats, propose the cylinder's metal.
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