1a. ) Complete the table with signs and general values for K (ie: K<1 or K>1)
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Always spontaneous |
Always nonspontaneous |
Spontaneous at high temperatures |
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ΔG |
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ΔH |
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ΔS |
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K |
2. Calculate the boiling point (in K) for the following:
X2 (l) --) X2 (g) ΔH = +35 kJ ΔS = + 215 J/K
(HINT: what does ΔG equal when a reaction switches from spontaneous to nonspontaneous?)
1b. ) Trick question (refer to the table in #1): at what temperature does the following reaction become spontaneous?
A ---) B ΔH = -40.5 kJ ΔS = + 150 J/K
| Always spontaneous | always non spontaneous | Spontaneous at High T | |
| ∆G | - | + | _ |
| ∆H | - | + | + |
| ∆S | + | - | + |
| K | >1 | <1 | >1 |
2) Tb = 35×1000/215
=> 162.8 K = 163 K
3) T = 40.5×1000/150
=> 270
1a. ) Complete the table with signs and general values for K (ie: K<1 or K>1)...
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