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1. Which statement is FALSE?
DS increases as pressure decreases
for an ideal gas, enthalpy is not pressure-dependent
the lowest value of free energy occurs at equilibrium
DS increases as volume increases
all statements are true

2. If an endorthermic reaction is spontaneous at 298 K, which of the following must be true for the reaction?
DG is greater than zero
DG is greater than zero
DG and DH are greater than zero
DH and DS are greater than zero
DG, DH, DS are all greater than zero

3. For the dissociation reaction of the acid HF: HF<-->H++ F -
DS is observed to be negative. The BEST explanation for this is:

This is the expected result since each HF molecule produces two ions when it dissassociates
Hydration of the ions produces the negative value of DS.
The reation is expected to be exothermic and thus D should be negative.
The reaction is expected to be endothermic and thus D should be negative.
None of these can explain the negative value of DS.

4. Which of these statements is false?
For a spontaneous reaction DG is negative
Independent of T, a reaction must be spontaneous if DH = 0 and DS is positive
A spontaneous reaction is always fast
A spontaneous reaction occurs without outside intervention
None of the above is false

5. For the gas sample B, this reaction is endothermic: B-->2B. The reaction is:
always spontaneous
only at high temperatures
only at low temperatures
never spontaneous
none of the above

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