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Question
Hydrogen gas is a non-polluting fuel. Hydrogen gas may be prepared by electrolysis of water.2 H2O(
) 2 H2(g) + O2(g)Predict the signs of DrH and DrS for the production of hydrogen gas by electrolysis of water.
A.DrH > 0 and DrS > 0
B.DrH < 0 and DrS > 0
C.DrH > 0 and DrS < 0
D.DrH < 0 and DrS < 0
E.DrH = 0 and DrS < 0
Answer
This answer is hidden. It contains 2 characters.
Related questions
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What is the distance, in atomic radii, along any edge of a body-centered unit cell?
A.
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If a metal crystallizes in a primitive cubic lattice, each metal atom has ____ "nearest neighbors."
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Arrange the three common unit cells in order from least dense to most dense packing.
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Which equation represents the number of atoms in a body-centered cubic unit cell?
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C.
D.
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Q:
The solubility product equilibrium constant, Ksp, of silver bromide is 5.4 10-13 at 298 K.
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Q:
What is the equilibrium constant for reaction below at 25 C? (R = 8.314 J/Kmol)2 NO(g) + O2(g) 2 NO2(g)given DfG [NO(g)] = +86.6 kJ/mol and DfG [NO2(g)] = +51.2 kJ/mol.A.3.9 10-13B.1.0C.2.6 1012D.1.6 106E.3.8 1028
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All of the following relationships are true EXCEPT
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Q:
Calculate DrG for the combustion of benzene at 325 K.2 C6H6() + 15 O2(g) 12 CO2(g) + 6 H2O()Species DfH (kJ/mol) S (J/Kmol)C6H6() 49.0 173.3O2(g) 0 205.1CO2(g) -393.5 213.7H2O() -285.8 67.0A.-6386 kJ/mol-rxnB.-6078 kJ/mol-rxnC.-7251 kJ/mol-rxnD.-8611 kJ/mol-rxnE.+1431 kJ/mol-rxn
Q:
If a chemical reaction is exothermic, but not spontaneous, which of the following must be true?
A.DrG > 0, DrS > 0 and DrH > 0
B.DrG < 0, DrS > 0 and DrH > 0
C.DrG > 0, DrS < 0 and DrH > 0
D.DrG < 0, DrS < 0 and DrH < 0
E.DrG > 0, DrS < 0 and DrH < 0