Please read the question properly before answering:
1. A process that occurs without any outside intervention is called
a. spontaneous process
b. non-spontaneous process
c. reversible reaction
d. irreversible reaction
2. A reaction in which the change in the system is made in such a way that the system can be restored to its original state by exactly reversing the change.
a. spontaneous process
b. non-spontaneous process
c. reversible reaction
d. irreversible reaction
3. Which of the following is reversible process?
a. melting of ice at 0oC and 1 atm
b. melting of ice at 25oC and 1 atm
c. evaporation of water at 25oC and 1 atm
d. freezing of water at -10oC and 1 atm
4. Which of the following is non-spontaneous process?
a. A waterfall runs downhill.
b. A lump of sugar dissolves in a cup of hot coffee.
c. Heat flows from hotter objects to a colder one.
d. Melting of ice at -5oC.
5. Which has the lowest entropy at a given temperature?
a. H2(g)
b. H2O(l)
c. O2(g)
d. H2O(s)
6. Which process involves a decrease in entropy of the system?
a. mixing of aqueous solution of NaCl and KNO3 together
b. spreading grass seed on a lawn
c. raking and bagging leaves in the fall
d. raking and burning leaves in the fall
7. Which of the following reactions shows a positive value of entropy?
a. H2O(l) → H2O(g)
b. Ag+(aq) + Cl-(aq) → AgCl(s)
c. 4Fe(s) + 3O2(g) → 2Fe2O3(s)
d. CaO(s) + CO2(g) → CaCO3(s)
8. How many of the following processes involve a decrease in disorder: humidifying dry air; distilling crude oil to gasoline, fuel oil; filtering solid impurities out of a mixture; adding sand to water?
a. 1
b. 2
c. 3
d. 4
9. Which has the highest entropy?
a. H2O(g) at 150oC
b. H2O(l) at 100oC
c. H2O(g) at 100oC
d. H2O(s) at -50oC
10. During a chemical process the system becomes more ordered. What is the sign of the entropy of the system for this process?
a. positive
b. negative
c. equals 0
d. unpredicted
11. The normal boiling point of ethanol, C2H5OH is 78.3oC and its molar enthalpy of vaporization, ∆Hvap is 38.56kJ/mol. What is the change in entropy when 68.3 g of C2H5OH(g) at 1 atm pressure condenses to liquid at the normal boiling point?
a. 163 J/K
b. -163J/K
c. 244 J/K
d. -244J/K
12. It is a system where there is no exchange of matter and energy with its surroundings.
a. open system
b. closed system
c. isolated system
d. open and closed system
13. What is the value of ∆Suniv for a reversible process?
a. equals zero
b. greater than zero
c. less than zero
d. unpredicted
14. What is the value of ∆Suniv for a irreversible process?
a. equals zero
b. greater than zero
c. less than zero
d. unpredicted
15. Which statement is correct?
a. The entropy of a pure substance is greater in the liquid state than in the gaseous state.
b. The entropy of a pure substance in a given state decreases as the temperature rises.
c. Entropy decreases when ethanol dissolves in water.
d. A bottle of carbonated water has lower entropy than the same masses of carbon dioxide gas and distilled water.
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