A/1 * b/c = d you discover a chemical reaction that produces 2 moles of valuable propane for every 7 moles of carbon supplied. essentially, this is an exchange rate of 2 moles of propane for every 7 moles of carbon. if you have 1.4 moles of carbon, how many moles of propane can you produce using this reaction?

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

indium, and thallium have three electrons i think