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Give the molecular formula of benzene. Give the Kekule structure of benzene and then explain why this structure is not correct. Give the accepted structure for benzene (5 marks).

Molecular formula: C₆H₆The Kekule structure (draw on whiteboard in session) - has the hexagonal shape of the ring, with a carbon=carbon double bond on every other carbon-carbon link....

Answered by Ben S. • Chemistry tutor

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Explain the trend in ionization energy down a group of the periodic table.

Ionization energy is the energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions. This is the following process;
X _g ---> ...

Answered by Euan W. • Chemistry tutor

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How can I apply the knowledge I learn in lessons to tougher exam style questions ?

The million dollar question when it comes to chemistry and is often the difference between a good grade and a great grade. The basis of this is to consolidate your basic concepts, make sure those are inst...

Answered by • Chemistry tutor

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Potassium Chlorate(VII) decomposes to produce Potassium Chloride and Oxygen. Using the following data calculate the enthalpy change of this decomposition: Enthalpy of formation(KClO4) = -430 kJ mol-1, Enthalpy of formation(KCl) = -440 kJ mol-1

Firstly the equation of this decomposition should be worked out to be the following
KClO₄(s) --> KCl(s) + 2O₂(g)
The enthalpy of formation has been given for both KClO<...

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Explain why ionic compounds (e.g. NaCl) are soluble, and why they conduct electricity in this state.

Ionic compounds have a 'giant' ionic lattice structure. 'Giant' just essentially means that a basic unit is being repeated. In the case of NaCl, the ionic lattice would consist of the ions Na+ and Cl-. Wa...

Answered by • Chemistry tutor

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