The slope of the feed line in distillation opeartion is given by (where, q = fraction of the feed stream that is liquid.)
A
$$ - {\text{q}}$$
B
$$ - \frac{{\text{q}}}{{1 - {\text{q}}}}$$
C
$$ - \frac{{\text{q}}}{{{\text{q}} - 1}}$$
D
None of these
Correct Answer: $$ - \frac{{\text{q}}}{{1 - {\text{q}}}}$$