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28 Cards in this Set
- Front
- Back
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What would you expect the enthalpy change of benzene to be? |
-360 |
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What actually is benzenes enthalpy change? |
-209 |
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What does benzenes enthalpy change tell us about benzenes delocalised system? |
Has much less energy than if the electrons weren't delocalised |
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What type of reactions would you expect benzene to undergo? |
Addition |
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What type of reaction does benzene actually undergo? |
Electrophillic substitution |
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What is the exception reactant with Benzene? |
Hydrogen |
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What does benzene undergo? |
Nitration Acylation |
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What conditions do nitration of benzenes occur in? |
50/50 H2SO4 and HNO3 Reflux |
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Nitric acid is weaker than H2SO4 and so during nitration acts as what? |
A base |
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What are the products of nitrating a benzene? |
Nitrobenzene Water |
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Acylation of Benzene occurs under what conditions and with what catalyst? |
Reflux AlCl3 |
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What does the AlCl3 catalyst do during acylation of benzene? |
Accept a Cl- form the chloroalkane |
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What are the products of acylation of benzene?
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HCl
Chlorobenzene |
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During Nitration and Acylation why is it important to keep temperature under 50? |
Prevent further substitution |
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What is nitrobenzene mainly used to make? |
Phenylamine |
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How is phenylamine produced? |
Reduce nitrobenzene with SnCl2 under reflux |
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Is Phenylamine a strong base?
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No
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Why is Phenylbenzene not a strong base? |
N lone pair is absorbed by the benzene |
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What does the delocalised system of benzene have an effect on? |
Stability |
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Benzenes delocalised system makes a molecule more what? |
Stable |
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How can the stability of benzene be measured? |
Measure enthalpy of hydrogenation |
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Are benzenes reaction endothermic or exothermic? |
Exothermic |
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What is the bond length of molecules in benzene? |
0.142NM |
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Benzenes electrons are what? |
Delocalised |
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What are benzenes bond angles? |
120 |
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A molecule containing benzene can be described as what? |
Aromatic |
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What is the formula for benzene? |
C6H6 |
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What is benzenes IUPAC name? |
Cyclo-1,3,5-triene |
