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1. 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

2. For the phase change of liquid to solid, DS is:
0
positive
negative
positive at high temperature
none of the above

3. DS for the universe is:
always positive
sometimes positive
always negative
sometimes negative
constant

4. 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.

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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