Fractionation of Crude Oil Select the correct ranking of the following alkanes according to the height reached in a fractionating column, highest first: butane, heptadecane, dodecane, ethane, decane Select the correct ranking of the following alkanes according to the height reached in a fractionating column, highest first: butane, heptadecane, dodecane, ethane, decane
A. ethane > butane > decane > dodecane > heptadecane
B. heptadecane > > dodecane > decane butane > ethane
C. ethane > butane > decane> heptadecane >
D. dodecane butane > ethane > decane > dodecane > heptadecane

A. ethane > butane > decane > dodecane > heptadecane

Explanation:

In fractionating column, crude oil is separated by means of fractional distillation due to the wide range of boiling point of the crude products such as ethane, propane, butane pentane etc.

The product with the least weight rises to top height while the product with highest weight will move down.

For the given hydrocarbon products, the ranking according to their molecular weight, starting with the lighter product to heavier product is

ethane (C2), butane (C4), decane(C10), dodecane (C12), heptadecane(C17).

Thus, the correct ranking, starting with the product that will rise highest is ethane > butane > decane > dodecane > heptadecane

i do not get it   at all