Answer to Question #60113 in Physical Chemistry for joseph orobiyi

Question

9 Which of the following involves a decrease in entropy?
the sublimation of carbon dioxide
the dissolution of NaCl in water
the evaporation of ethanol
the freezing of liquid water into ice



10 A statement of the second law of thermodynamics is that
the entropy of the universe is continually increasing.
energy is conserved in a chemical reaction.
spontaneous reactions are always exothermic.
the enthalpy of reaction is the difference between product and reactant
enthalpies.



11 Of the following product-favoured processes, which are endothermic?
1. the combustion of methane to produce water and carbon dioxide. 2. the
expansion of an ideal gas. 3. the melting of ice at temperatures greater
than $0^ºC$.
1 only
2 only
3 only
2 and 3

Answer 1

9. the freezing of liquid water into ice involves a decrease in entropy.
10. A statement of the second law of thermodynamics is that the entropy of the universe is continually increasing.
11. 3 only. The expansion of ideal gas is energy neutral (although expansion of most real gases are endothermic).