3. A student goes to the cafeteria to get an iced tea. He puts 3 ice cubes (approximately 20.0 mL each, Sice = insulated cup and then fills the cup with 375 mL of tea. The tea is coming from a machine at room temperature, which is 22,5°C. The student is so immersed in studying chemistry that he forgets about his drink. When he finally goes to take his first drink, he notices that the ice has just melted. At what temperature is his iced tea? Assume the density of ice is that of water. It may be helpful to plot the temperatures on the heating curve below. lH,0=333 J/g. 2.100 J/g °C) from the ice machine (at – 15.0°C) into a well- %3D

3. A student goes to the cafeteria to get an iced tea. He puts 3 ice cubes (approximately 20.0 mL each, Sice = insulated cup and then fills the cup with 375 mL of tea. The tea is coming from a machine at room temperature, which is 22,5°C. The student is so immersed in studying chemistry that he forgets about his drink. When he finally goes to take his first drink, he notices that the ice has just melted. At what temperature is his iced tea? Assume the density of ice is that of water. It may be helpful to plot the temperatures on the heating curve below. lH,0=333 J/g. 2.100 J/g °C) from the ice machine (at – 15.0°C) into a well- %3D

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter9: Energy And Chemistry

Section: Chapter Questions

Problem 9.38PAE: 9.38 The energy densities of various types of coal are listed below: Anthracite 35 kJ/g...

See similar textbooks

Similar questions

9.83 A student performing a calorimetry experiment combined 100.0 mL of 0.50 M HCl and 100.0 mL of 0.50 M NaOH in a coffee cup calorimeter. Both solutions were initially at 20.0°C, but when the two were mixed, the temperature rose to 23.2°C. (a) Suppose the experiment is repeated in the same calorimeter but this time using 200 mL of 0.50 M HCl and 200.0 mL of 0.50 M NaOH. Will the T observed he greater than, less than, or equal to that in the first experiment, and why? (b) Suppose that the experiment is repeated once again in the same calorimeter, this time using 100 mL of 1.00 M HCl and 100.0 mL of 1.00 M NaOH. Will the T observed he greater than, less than, or equal to that in the first experiment, and why?
The enthalpy of vaporization for water is 40.65 kJ mol-1. As a design engineer for a project in a desert climate, you are exploring the option of using evaporative cooling. (a) If the air has an average volumetric heat capacity of 0.00130 J cm-3 K-1, what is the minimum mass of water that would need to evaporate in order to cool a 5 m? 5 m room with a 3 m ceiling by 5°F using this method? (b) Is this a spontaneous or nonspontaneous process?
Are any of the following exothermic processes not spontaneous under any circumstances? (a) Snow forms from Liquid water. (b) Liquid water condenses from water vapor. (c) Fossil fuels burn to form carbon dioxide and water. (d) Monomers react to form a polymer.
A student performing a calorimetry experiment combined 100.0 ml. of 0.50 M HCI and 100.0 ml. of 0.50 M NaOH in a StyrofoamTM cup calorimeter. Both solutions were initially at 20.0 C, but when the two were mixed, the temperature rose to 23.2 C (a) Suppose the experiment is repeated in the same calorimeter but this time using 200 mL of 0.50 M HCl and 200.0 ml of 0.50 M NaOH. WIII the AT observed be greater than, less than, or equal to that in the first experiment, and why? (b) Suppose that the experiment is repeated once again in the same calorimeter, this time using 100 mL of 1.00 M HCI and 100.0 ml. of 1.00 M NaOH. Will the T observed be greater than, less than, or equal to that in the first experiment, and why?
Peanuts and peanut oil are organic materials and bum in air. How many burning peanuts does it take to provide the energy to boil a cup of water (250 mL of water)? To solve this problem, we assume each peanut, with an average mass of 0.73 g, is 49% peanut oil and 21% starch; the remainder is noncombustible We further assume peanut oil is palmitic acid, C16H32O2, with an enthalpy of formation of 848.4 kJ/mol. Starch is a long chain of C6H10O5 units, each unit having an enthalpy of formation of 960 kJ.
The decomposition of ozone, O3, to oxygen, O2, is an exothermic reaction. What is the sign of q? If you were to touch a flask in which ozone is decomposing to oxygen, would you expect the flask to feel warm or cool?
9.38 The energy densities of various types of coal are listed below: Anthracite 35 kJ/g Subbituminous 31 kJ/g Bituminous 28 kJ/g Lignite 26 kJ/g An unknown sample of one of these coals is burned in an apparatus with a calorimeter constant of 1.3 kJ/°C. When a 0.367-g sample is used, the temperature change is 8.75°C. Which type of coal is the sample?
A 500-g sample of one of the substances listed in Table 7-1 was heated from 25.2C to 55.1C, requiring 133 J to do so. Which substance was it?
10.59 The normal melting point of benzene, C6H6, is 5.5°C. For the process of melting solid benzene, what is the sign of each of the following? (a) H, (b) S, (c) Gat 5.5°C, (d) Gat 0.0°C, (e) Gat 25.0°C.
In a coffee-cup calorimeter, 100.0 mL of 1.0 M NaOH and 100.0 mL of 1.0 M HCI are mixed. Both solutions were originally at 24.6C. After the reaction, the final temperature is 31.3C. Assuming that all the solutions have a density of 1.0 g/cm3 and a specific heat capacity of 4.18 J/Cg, calculate the enthalpy change for the neutralization of HCl by NaOH. Assume that no heat is lost to the surroundings or to the calorimeter.
Nitric acid, HNO3, can be prepared by the following sequence of reactions: 4NH3(g)+5O2(g)4NO(g)+6H2O(g)2NO(g)+O2(g)2NO2(g)3NO2(g)+H2O(l)2HNO3(l)+NO(g) How much heat is evolved when 1 mol of NH3(g) is converted to HNO3(l)? Assume standard states at 25 C.
Use standard entropies and heats of formation to calculate G f at 25C for (a) cadmium(II) chloride (s). (b) methyl alcohol, CH3OH(l). (c) copper(I) sulfide (s).