A mixture of two high-boiling organic acids is to be separated from nonvolatile impurities by steam distillation at 373 K under a total pressure of 20 kPa. The organic acid mixture contains 30 mol% low boiling acid and 70 mol% high boiling acid and at 373 K the vapour pressures of the two acids are 2.7 kPa and 1.1 kPa, respectively. The acid mixture obeys Raoult's law and are immiscible with water. Determine the kilograms of steam required per kmol of acid recovered