Question

1. ) How does the number of theoretical plates effect the separation of a mixture of solutions. 2.) 7. You have a mixture of hexanes (BP 68°C) and heptane (98.42°Ç, what distillation technique should you use?

Answer 1

Answer : 1) number of theoretical plates (N) is the direct indication of column efficiency. Columns with high plate numbers are considered to be more efficient, that is, have higher column efficiency, than columns with a lower plate count. Mathematical expression

N = 5.45 (t_R / w_h)²

where N = number of theoritical plates

t_R = retension time

w_h = peak width at half height

speration of a mixture of solution is more efficient with a column of high number of theoretical plates

answer 2) distillation can be used to sperate hexane from heptane because the boling point difference between hexanes and heptane is almost 30 degree which is quite good

by just simple distillation means heating the mixture around 70^oC we can collect pure hexane leaving behind heptane whose boiling point is 98.42^oC