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When Karl Kaveman adds chilled grog to his new granite mug, he removes 10.9 kJ of energy from the mug. If it has a mass of 625 g and was at 25°C, what is its new temperature? Specific heat capacity of granite = 0.79 J/(g·K)


A) 3°C
B) 14°C
C) 22°C
D) 47°C
E) none of the above

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Clearly state the thermodynamic standard state of a. an element or compound. b. a solute.

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a. Standard state is the stabl...

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a. Define, or explain fully what is meant by the standard enthalpy of formation of a substance, f.. b. What is the standard state of the element oxygen? c. Write down in full the formation reaction for liquid ethanol, C2H5OH(l). The equation should be balanced and should indicate the physical state of each substance.

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a. f is the enthalpy ch...

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A system receives 575 J of heat and delivers 425 J of work. Calculate the change in the internal energy, E, of the system.


A) -150 J
B) 150 J
C) -1000 J
D) 1000 J
E) 575 J

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A system that does no work but which receives heat from the surroundings has


A) q < 0, E > 0.
B) q > 0, E < 0.
C) q = E.
D) q = -E.
E) w = E.

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Calculate q when 28.6 g of water is heated from 22.0°C to 78.3°C.


A) 0.385 kJ
B) 1.61 kJ
C) 6.74 kJ
D) 9.37 kJ
E) 1.61 × 103 kJ

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A system which undergoes an adiabatic change and has work done on it by the surroundings has


A) w = E.
B) w = -E.
C) w > 0, E < 0.
D) w < 0, E > 0.
E) w > E.

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The only way in which a system can do work on the surroundings is by expansion against the external pressure.

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For all processes, both q and w will have the same sign.

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The dissolution of barium hydroxide in water is an exothermic process. Which of the following statements is correct?


A) The enthalpy of solid barium hydroxide plus pure water is less than that of the solution, at the same temperature.
B) The enthalpy of solid barium hydroxide plus pure water is greater than that of the solution, at the same temperature.
C) The enthalpy of solid barium hydroxide plus pure water is the same as that of the solution, at the same temperature.
D) The temperature of the solution is lower than of the barium hydroxide and water before mixing.
E) When barium hydroxide dissolves in water, the system does work on the surroundings.

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An ideal gas (the system) is contained in a flexible balloon at a pressure of 1 atm and is initially at a temperature of 20.°C. The surrounding air is at the same pressure, but its temperature is 25°C. When the system has equilibrated with its surroundings, both systems and surroundings are at 25°C and 1 atm. In changing from the initial to the final state, which one of the following relationships regarding the system is correct?


A) .E < 0
B) .E = 0
C) .H = 0
D) w > 0
E) q > 0

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Cold packs, whose temperatures are lowered when ammonium nitrate dissolves in water, are carried by athletic trainers when transporting ice is not possible. Which of the following is true of this reaction?


A) .H < 0, process is exothermic
B) .H > 0, process is exothermic
C) .H < 0, process is endothermic
D) .H > 0, process is endothermic
E) .H = 0, since cold packs are sealed

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The enthalpy (H) of liquid water is greater than that of the same quantity of ice at the same temperature.

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A system initially has an internal energy E of 501 J. It undergoes a process during which it releases 111 J of heat energy to the surroundings, and does work of 222 J. What is the final energy of the system, in J?


A) 168 J
B) 390 J
C) 612 J
D) 834 J
E) cannot be calculated without more information

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In a reaction with high energy reactants and low energy products, q is negative.

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Which one of the following is a correct formation reaction?


A) C(diamond) C(graphite)
B) H2(g) + O(g) H2O(l)
C) C(graphite) + 4H(g) CH4(g)
D) 6C(graphite) + 6H2O(s) C6H12O6(s)
E) 2C(graphite) + 3H2(g) + Which one of the following is a correct formation reaction? A)  C(diamond)  <font face= symbol ></font> C(graphite)  B)  H<sub>2</sub>(g)  + O(g)  <font face= symbol ></font> H<sub>2</sub>O(l)  C)  C(graphite)  + 4H(g)  <font face= symbol ></font> CH<sub>4</sub>(g)  D)  6C(graphite)  + 6H<sub>2</sub>O(s)  <font face= symbol ></font> C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>(s)  E)  2C(graphite)  + 3H<sub>2</sub>(g)  +   O<sub>2</sub>(g)  <font face= symbol ></font> C<sub>2</sub>H<sub>5</sub>OH(l) O2(g) C2H5OH(l)

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A piece of copper metal is initially at 100.0°C. It is dropped into a coffee cup calorimeter containing 50.0 g of water at a temperature of 20.0°C. After stirring, the final temperature of both copper and water is 25.0°C. Assuming no heat losses, and that the specific heat (capacity) of water is 4.18 J/(g·K) , what is the heat capacity of the copper in J/K?


A) 2.79 J/K
B) 3.33 J/K
C) 13.9 J/K
D) 209 J/K
E) none of the above

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Which one of the following statements about standard states is incorrect?


A) The standard state of a solid compound is the pure solid.
B) The standard state of a liquid compound is the pure liquid.
C) The standard state of a gaseous compound is the gas at a pressure of 1 atmosphere.
D) The standard state of an aqueous solute is a saturated solution in water.
E) The standard state of an element is the form in which it is stable at 1 atm and a specified temperature, usually 25°C.

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A system delivers 225 J of heat to the surroundings while delivering 645 J of work. Calculate the change in the internal energy, E, of the system.


A) -420 J
B) 420 J
C) -870 J
D) 870 J
E) -225 J

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Standard heats (enthalpies) of formation of compounds, f, may be positive or negative.

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