Astream that is 3 wt% b and the 97 wt% c, and a stream that contains only a and b (5,300 kg/hr total), are fed to a column. three product streams emerge: the overhead is 100% a. the bottom stream is 60 wt% b and 40 wt% c. the middle stream is 70 wt% a and the rest b and c and flows at 1,200 kg/hr. how many material balances can be written on the overall system?

Explanation:

Three balances can be written.

Mass of A into the column = mass of A out of the column

Mass of B into the column = mass of B out of the column

Mass of C into the column = mass of C out of the column

There are four unknowns: mass flow of the first feed stream, mass flow of the overhead stream, mass flow of the bottom stream, and percent B or C of the middle stream.

Since there are more unknowns than equations, there is not enough information to solve the equations.