Predict the relative rates for the reaction of butadiene and (a) ethene, (b) methyl propenoate, (c) maleic anhydrid.

To predict the relative rates of a reaction between different reactants, we need to consider several factors. The relative rates depend on the concentration of reactants, their reaction mechanism, and any catalysts or inhibitors involved. Additionally, the relative rates can be influenced by temperature, pressure, and other environmental conditions. Without specific details about the reaction conditions, it's difficult to give an accurate prediction.

However, I can provide you with some general information about the reactivity of the reactants you mentioned.

(a) Ethene: Ethene is an unsaturated hydrocarbon with a double bond between two carbon atoms. It is relatively reactive due to the presence of this double bond, which can undergo addition reactions. Butadiene, on the other hand, is a conjugated diene with two double bonds separated by a single bond. The presence of conjugation makes it more reactive compared to ethene. Therefore, under normal conditions, it is expected that butadiene would react with ethene faster.

(b) Methyl propenoate: Methyl propenoate is an ester and contains a carbonyl group (C=O) in addition to a double bond. The presence of the carbonyl group makes it less likely to undergo addition reactions, compared to a simple alkene like ethene. Therefore, it can be expected that the reaction of butadiene with methyl propenoate would be slower than with ethene.

(c) Maleic anhydride: Maleic anhydride is a cyclic compound containing two carbonyl groups, forming a five-membered ring structure. It is highly reactive due to the presence of these carbonyl groups, which can participate in addition reactions. Therefore, it is expected that butadiene would react relatively faster with maleic anhydride compared to both ethene and methyl propenoate.

Remember, these predictions are based on general reactivity trends and assumptions. To get more accurate predictions, it is necessary to have specific reaction conditions and experimental data.