Question

A/1 * B/C = D

Answer 1

As per the problem 2 moles of propane are produced when 7 moles of carbon are supplied

so if we supply 1 mole of carbon the moles of propane obtained = 2 /7

if we supply 1.4 moles of carbon the moles of propane obtained = 2 X 1.4 /7 = 0.4 moles of propane

Hence answer is  propane we can produce using this reaction = 0.4 moles from 1.4 moles of carbon