Question

What mass of phosphorus and of chlorine is needed to produce 87 g of pentachloride if the reaction yield is 60%?

Answer 1

Hey there!

theoretical yield =  (87* 100 ) / 60 = 145 g of phosphorous pentachloride

the reaction for this process is :

molar mass P2O5 => 239.2125 g/mol

molar mass P4 => 123.90 g/mol

molar mass Cl2 => 70.9060 g/mol

P4 + 5 Cl2   -------------->  2 P2Cl5

moles of P2O5 :

145 g / 239.2125  => 0.6062 moles of P2O5

Therefore:

moles of P4 = 0.6062 mol / 2 =>  0.3031 moles

moles of Cl2 = 5/2 * 0.6062 mol  = 1.5154 moles

mass of P4 ( phosphours ) = 0.3031 mol * 123.90 => 37.554 grams

mass of Cl2 ( chlorine ) = 1.5154 mol  * 70.9060 => 107.45 grams

Hope That helps!