It would be 12.4 moles of HCL because you multiply 6.2 by how many moles of HCL in te equation then divide it by how many moles of h2 in the equation so you multiple 6.2 by 2 moles because there’s two moles of HCL which gives you 12.4 then you divide it by one because in the equation there is only 1 mole of H2