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Explain the relative resistance to bromination of benzene compared with alkenes.

Benzene has a delocalised pi system in which p orbitals of all carbon atoms overlap above and below the carbon ring. Alkenes, however, have localised pi-orbital overlaps between two carbon atoms. The elec...

Answered by Jasmine W. • Chemistry tutor

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Why does graphite conduct electericity but diamond does not if both substances have a giant covalent structure?

Graphite consists of carbon atoms joined together. Since carbon has 4 unpaired electrons in it's outer shell, it can form a maximum of 4 covalent bonds by sharing each of it's unpaired electrons with anot...

Answered by Prithi N. • Chemistry tutor

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Use the following data to explain why NaCl is soluble in water: ∆H = +31 kJmol-1, S(Na+(aq)) = 320.9 JK-1mol-1, S(Cl-(aq)) = 56.5 JK-1mol-1, S(NaCl(s)) = 72.1 JK-1mol-1 Are there any temperatures at which you would not expect NaCl to dissolve?

This is a nice simple calculation question which explores some basic thermodynamic principles and begins to apply them to simple reactions (in this case, solid salt dissolving in water) allowing predictio...

Answered by Kieran R. • Chemistry tutor

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How can one differentiate between the organic compounds propanal (CH3CH2CHO) and propanone (CH3COCH3)?

React a sample of each compound with Tollens reagent. The aldehyde (propanal) will be oxidised to a carboxylic acid (propanooic acid) and will form a silver mirror. No change will be observed with the ket...

Answered by Julie T. • Chemistry tutor

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What is the difference between exothermic and endothermic?

Exothermic and Endothermic are opposite reactions. All reactions need energy to be put in to start them off, this is called the activation energy, but th...

Answered by • Chemistry tutor

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