I calculated the partial pressure to be 16.1 - and it was wrong?

Consider the following equilibrium reaction at #256^circC#.
#SbCl_(5"(g)")⇌SbCl_("3(g)") + Cl_(2"(g)")#

If the equilibrium constant in terms of concentrations (#K_c#) is #3.7 xx 10^-2#, calculate the equilibrium constant in terms of partial pressures (#K_p#).

1 Answer
Feb 20, 2018

#K_p~~163#

Explanation:

#K_c# and #K_p# are linked by the following reaction:
#K_p=K_c(RT)^(Deltan)#, where:

  • #K_c# = equilibrium constant in terms of pressure
  • #R# = gas constant (#8.31"J"# #"K"^-1# #"mol"^-1#)
  • #T# = absolute temperature (#K#)
  • #Deltan="Number of moles of gaseous products"-"Number of moles of gaseous reactants"#

#K_c=3.7*10^-2#
#R=8.31"J"# #"K"^-1# #"mol"^-1#
#T=256+273=529K#
#Deltan=1#

#K_p=(3.7*10^-2)(529*8.31)^1=(3.7*10^-2)(529*8.31)=162.65163~~163#