(a) What is meant by the terms

(i) a global reaction;

(ii) an elementary reaction;

(iii) a reaction mechanism.

(b) Describe the steps required to form a chain reaction and explain why chain reactions are important in combustion.

(c) A reaction is found to be 25 times faster at \(400 \mathrm{~K}\) than at \(300 \mathrm{~K}\). Measurements of the temperature exponent yielded a value of 0.7 . Calculate the activation energy of the reaction. How much faster will the reaction be at \(1000 \mathrm{~K}\) ?