Question

If 5 moles of P4 reacted with 22 moles Cl2 according to the above reaction, determine:

a. How many moles PCl3 are produced ________________
b. How many moles of P4 are left in excess after the reaction (if any) ________________
c. How many moles of Cl2 are left in excess after the reaction (if any) ________________

Answer 1

`P_4+6Cl_2\rightarrow 4PCl_3`

a) By stoichoimetry If 6 moles of
`Cl_2` gives 4 mole of
`PCl_3` , then 22 moles of
`Cl_2` will give:
`(4)/(6)* 22=(44)/(3)=14.66` moles of
`PCl_3`

b) If 6 moles of
`Cl_2` reacts with one mole of
`P_4` , then 22 moles of
`Cl_2` will react :
`(1)/(6)* 22=(11)/(3)=3.66` moles of
`P_4`

Moles of
`P_4` left after the reaction =
`5-3.66=(4)/(3)=1.34` moles.

c) 0 Moles of
`Cl_2` , since it is present in less amount it will get completely consumed in the reaction. Hence, it is limiting reagent.