20.0kg of CaC2 =20.0×10364=312.5 moles of CaC2
From the above reactions it is evident that 1 mol CaC2 gives 1 mol of acetylene, of which n moles combines with n moles of H2 to give polyethylene (n molecules of C2H4 or polymerized C2H4 ).
Hence 312.5 moles of CaC2 will give 312.5 moles of C2H4 =312.5×28=8750 g or 8.75 kg
OR the polyethylene formed is 8.75 kg.