5.12 - I can recall the problems associated with the fractional distillation of crude oil.

a. When crude oil undergoes ________ ________ there are too many ________ chain hydrocarbons (eg ________) produced and not enough ________ chain hydrocarbons (eg ________).
b. To solve these problems the ________ chain hydrocarbons undergo a chemical reaction called ________. (see objective 5.13)