Phosphorus pentachloride dissociates as follows in a closed reaction vessel.
`PCl_5(g) hArr PCl_3(g) +Cl_2(g)`
If total pressure at equilibrium of the reactions mixture is P and degree of dissociation of `PCl_5`is x, the partial pressure of `PCl_3` will be:

Options

A. `((x)/(x+1))P`
B. `((2x)/(1-x))`
C. `((x)/(x-1))P`
D. `((x)/(1-x))P`

Answer

A

Explanation

`PCl_(5(g)) Leftrightarrow PCl_(3(g))+Cl_(2(g))`
`{:(,at t=0, 1,0,0),(,"Reacted and formed",x,x,x),(,"At equilibrium",1-x,x,):}`
total moles =1-x+x+x=1+x
Total pressure =P
partial pressure of `PCl_(3)=((x)/(1+x))P`