* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Vocabulary - cloudfront.net
Calorimetry wikipedia , lookup
Heat exchanger wikipedia , lookup
Equipartition theorem wikipedia , lookup
Thermoregulation wikipedia , lookup
Temperature wikipedia , lookup
Heat capacity wikipedia , lookup
Heat equation wikipedia , lookup
Thermal radiation wikipedia , lookup
Conservation of energy wikipedia , lookup
Internal energy wikipedia , lookup
Copper in heat exchangers wikipedia , lookup
Countercurrent exchange wikipedia , lookup
Chemical thermodynamics wikipedia , lookup
R-value (insulation) wikipedia , lookup
First law of thermodynamics wikipedia , lookup
Heat transfer wikipedia , lookup
Heat transfer physics wikipedia , lookup
Thermodynamic system wikipedia , lookup
Thermal conduction wikipedia , lookup
Second law of thermodynamics wikipedia , lookup
Name ______________________________ Thermodynamics Unit Study Guide Chap. 21-24 Vocabulary Temperature Heat Internal energy Thermal equilibrium Specific heat capacity Convection Conduction Radiation Heat of fusion Heat of vaporization Thermal Expansion Adiabatic Heat engine Entropy Thermodynamics Problems 1. The hottest temperature ever recorded on a planet was 864 ºF on Venus by the Soviet Venera probe and the U.S. Pioneer probe. The coldest place in the solar system is Pluto where the temperature is estimated at -360.0 ºF. Calculate each of these temperatures in degrees Celsius and Kelvin. 462 ºC, 735 K -217 ºC, 54 K 2. A man consumes 2,500 Calories (food calories) in one day assuming that all of this energy was used, and converted into heat, how much heat (in J/s) did he give off that day? 2500 Cal Day 1 day 24 hr 1 hr 3600 s 4.18J 1 cal = .12 J/s 3. Calculate the number of calories of heat needed to change 340 mL of water by 50 C. Recall that 100 mL of water = 100 g of water. Q = mc∆T = 340 g x 1 cal/g C x 50 C = 17,000 calories 4. A 50 gram piece of aluminum is heated to 100C and then dropped into cool water where the aluminum’s temperature drops to 30C. How many calories does the aluminum loose to the water? (Specific heat capacity Al = 0.215 cal/gC). (50 g) x (.215 cal/ gC) x (70) = 753 calories lost 5. What mass of water will give up 96 calories when its temperature is changed from 90C to 60C? 6. Q = mc∆T 7. 96 = m (1 cal/g C) x (30 C) 8. 3.2 g = m 9. As he rides the train to work on a -4.0 ºC winter day, Mr. Shapiro notices that he can hear the click of the train going over spaces between the rails. Six months later, on a 30.0 ºC summer day, the rails are pushed tightly together and he hears no click. IF the rails are 5.00 m long, how large a gap is left between the rails on the cold winter day? (αsteel = 12 x 10-6 ºC-1). L = LαT = (5 m) x (12 x 10-6 ºC-1) x (34 ºC) = 2040 x 10-6 = 2.04 x 10-3 m 10. How much heat is absorbed when 45 g of H2O as ice at 0 C is converted into a liquid at 0 C? (45g) x (80 cal/g) = 3,600 cal 11. How much heat is released when 75 g of H2O vapor is condensed to a liquid? (75g) x (540 cal/g) = 40,500 cal 12. Calculate the Ideal efficiency of a heat engine that takes in energy at 450 K and expels it to a reservoir at 60 K. 86 % 13. Circle the letter that best describes what happens when heat is added to a system. a. Much of it is destroyed immediately b. It transforms to an equal amount of some other form of energy. c. Much of it is lost d. It is used to overcome friction 14. Is the following sentence true or false? The compression and expansion of gases within the cylinders of an automobile engine is nearly adiabatic. TRUE 15. What happens to a gas when it adiabatically expands and does work on its surroundings? ___It loses energy to the outside surroundings (loses internal energy) and cools. Very similar to what happened in the cloud chamber when the rubbing alcohol vapor rapidly expanded out of the opening. 16. Circle the letter that describes the adiabatic form of the first law of thermodynamics. a. pressure = constant b. energy out > energy in c. change in air temperature is directly proportional to the pressure change d. energy in = energy out + work Use the illustration below to answer the next question. 17. Circle the letter that describes the process that occurs to create the warm wind. a. adiabatic expansion b. adiabatic compression c. isobaric contraction d. thermal gain from land 18. Circle the letter of the thermodynamic law that states heat will never of itself flow from a cold object to a hot object. a. 1st Law b. 2nd law c. 3rd law d. 4th law 19. Is the following sentence true or false? Many heat engines are able to convert all heat input into mechanical energy output. FALSE 20. Is the following sentence true or false? No heat engine can have an ideal efficiency of 100%. TRUE 21. Circle the letter that best describes how the second law of thermodynamics applies to order and disorder. a. For all systems, overall order is constant. b. Natural systems tend toward a state of greater disorder. c. Natural systems are equally likely to become more ordered or more disordered d. All natural systems tend toward increasing disorder 22. A sample of gas is contained in a sealed flask. Circle the letter with the greatest disorder. a. The sample at 25 C in the sealed flask b. The sample at 50 C in the sealed flask c. The sample immediately after opening the flask d. The sample after it expands to fill the room 23. more a. b. c. d. Circle the letter of each example of increasing entropy. There may be than one answer. Gas molecules escaping from a bottle An unattended house breaking down A plant using energy from the sun to form new cells A breeze blowing papers off of your desk