Identify the nucleophile and the electrophile in the following acid–base reactions:
a.
b.

When a small piece of platinum is added to a mixture of ethene and hydrogen, the ­following reaction occurs:

Doubling the concentration of hydrogen has no effect on the reaction rate. Doubling the concentration of ethene also has no effect.

b. Write the unusual rate equation for this reaction.

c. Explain this strange rate equation, and suggest what one might do to accelerate the reaction.

How will the rate of the reaction between bromomethane and hydroxide ion be affected if the following changes in concentration are made?

c. The concentration of the alkyl halide is cut in half and the concentration of the nucleophile is doubled.

(a) On a reaction coordinate diagram, show why a general, one-step reaction is faster when a catalyst is employed.

(b) Why does a catalyst often allow a reaction to proceed at lower temperatures?

For the following acid–base pairs, (v) show a mechanism for the reaction; and (vi) draw a reaction coordinate diagram.

(f)

Within the following pairs, pick which reaction you would expect to be faster based on having a higher value of the frequency factor (A).

(b)

For the following acid–base pairs, (vi) draw a reaction coordinate diagram.

(e)

Parts (a)–(f) of this assessment refer to the rotation around the single bond of ethane.

(c) Write the rate law for this reaction.

All things being equal, would you expect a first-order reaction to be faster or slower than a second-order reaction?