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Chemistry

A Level

Name the three steps in free radical substitution and give an example equation for each

Initiation: Cl2 (+UV) -> Cl + Cl Propagation: Cl + CH4 -> HCl + CH3 Termination: CH3 + Cl -> CH3Cl

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A reaction, A + B -> C, is considered second order with respect to A and first order with respect to B. What is the effect of simultaneously doubling the concentration of A and B on the rate of reaction?

"second order with respect to A" tells us that doubling the concentration of A will cause the reaction rate to increase by a factor of 4."first order with respect to B" then tells us t...

Answered by HENRY J. • Chemistry tutor

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Discuss the 2 most-commonly encountered representations of benzene, providing an advantage and disadvantage for each

Kekule structure advantages: Useful for mechanistic understanding, can push arrows to advise likely regiochemistry. Disadvantages: ignores aromatic stablisation, drawn structure much higher energy than ac...

Answered by William H. • Chemistry tutor

3616 Views

What is meant by an ion being 'polarising' - and how does that determine if something is ionic/covalent?

The more polarising ion is the one that can distort the electron cloud of the other ion in the ionic bond more. The top of group two are the most ionising, since these have a small electron cloud and a bi...

Answered by Ben D. • Chemistry tutor

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Describe the Kekule and delocalised model of benzene and explain some of the reasons why the kekule is disproved

Kekule Model - 6 membered carbon ringComposed of carbon atoms joined together by alternating single and double bonds
Delocalised Model - A planr cyclic hydrocarbon composed of 6 carbon atoms and 6 hy...

Answered by Muhammad S. • Chemistry tutor

3069 Views