500kmol/h of a feed to a distillation column (stream 1] contains 70% methanol and 30% ethanol. 90% of the methanol in the feed [1] is recovered as the distillate from column 1
(stream 2] Given that the composition of methanol in stream [2] is 97%, and 99% of the remaining methanol in stream (3] is
removed as a distillate in stream [4]​

the answer is 75.0%.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.