Assignment:
Question 1. Calculate the maximum concentration (in M) of sulfide ions in a solution containing 0.181 M of lead ions. The Ksp for lead sulfide is 3.4 x 10-28.
a. 1.9 x 10-27
b. 9.4 x 10-28
c. 1.5 x 10-26
d. 3.0 x 10-25
e. 3.4 x 10-28
Question 2. A reaction that is spontaneous ___________.
a. will proceed as written without outside intervention
b. will be very rapid as written
c. will occur very slowly
d. is also spontaneous in the reverse direction
e. has an equilibrium position that lies very far to the left
Question 3. In a spontaneous process, __________.
a. the path between reactants and products is irreversible
b. the reverse process is also spontaneous
c. forward and reverse processes occur at the same rate
d. the reverse process occurs at a higher rate than the forward process
e. the path between reactants and products is reversible
Question 4. Which of the following is a reversible process?
a. Melting of ice at 0°C and 1 atm
b.Freezing of water at -10°C and 1 atm
c.Evaporation of water at 25°C and 1 atm
d.Freezing of water at -25°C and 1 atm
e.Melting of ice at 25°C and 1 atm
Question 5. Given the following table of thermodynamic data, determine the normal boiling point (in °C) of TiCl4.
Substance ΔHf° S°
TiCl4(g) -763.2 kJ/mol 354.9 J/mol-K
TiCl4(l) -804.2 221.9
a. 308.3
b. 41.0
c. 35.3
d. 273.3
e. 133.0
Question 6. Which equation represents a reaction that is decreasing in entropy as the reaction proceeds?
a. H2O(l) H2O(g)
b. 2C(s) + O2(g) 2CO(g)
c. CaCO3(s) CaO(s) + CO2(g)
d. 2H2(g) + O2(g) 2H2O(l)
e. 2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g)
Question 7. For which one of the following reactions should the sign of ΔS be negative?
a. C(s) + O2(g) CO2(g)
b. H2O(l) H2O(g)
c. NH3Cl(s) HCl(g) + NH3(g)
d.2NaCl(s) + H2SO3(aq) 2HCl(g) + Na2SO4(s)
e.2SO2(g) + O2(g) 2SO3(g)
Question 8. Consider a pure, crystalline solid being heated from absolute zero to some very high temperature. Which one of the following processes produces the greatest increase in the entropy of the substance?
a. Heating the liquid
b. Boiling the liquid
c. Heating the solid
d. Heating the gas
e. Melting the solid
Question 9. Given the following table of thermodynamic data, determine the ΔS° (in J/mol-K) for the reaction:
C2H2(g) + 2 H2(g) C2H6(g).
Substance S°
C2H2(g) 200.8 J/mol-K
C2H4(g) 219.4
C2H6(g) 229.5
H2(g) 130.58
a. -111.98
b. -101.88
c. -232.46
d. +101.88
e. +111.98
Question 10. Which species below has/have ΔG°f = 0?
a.Both Co(s) and H2(g)
b. HCo(PF3)4(g)
c. Co(s)
d. H2(g)
e. PF3(g)