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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: Studyinghard on November 08, 2010, 04:56:02 pm

Title: CSE 2008
Post by: Studyinghard on November 08, 2010, 04:56:02 pm

PCl5 ----> PCl3 + Cl2

0.8 mol is initially placed in 4L vessel at 400 degrees and allowed to come to equilibrium. At eq., 0.760 mol of chlorine forms. The constant is..

a) 3.61
b) 7.22
c) 14.4
d) 27.7

ty

Title: Re: CSE 2008
Post by: Xavier1234 on November 08, 2010, 05:22:17 pm

Quote from: Studyinghard on November 08, 2010, 04:56:02 pm

PCl5 ----> PCl3 + Cl2

0.8 mol is initially placed in 4L vessel at 400 degrees and allowed to come to equilibrium. At eq., 0.760 mol of chlorine forms. The constant is..

a) 3.61
b) 7.22
c) 14.4
d) 27.7

ty

A. 3.61M

Title: Re: CSE 2008
Post by: Studyinghard on November 08, 2010, 05:53:23 pm

calculations ?

Title: Re: CSE 2008
Post by: Xavier1234 on November 08, 2010, 05:57:23 pm

Initial of PCL₅ is 0.8mol.

the ratio is 1:1:1.

and the change in mol of Cl₂ is 0.76mol. that corresponds to 0.76 mol change for both PCl₅ and PCl₃ as well as per the equal ratio.

then subtract 0.8 by 0.76 = 0.04 mol at equilibrium for PCl₅.

then divide the 0.04 by 4L as per the volume and the 0.76 by 4L as well.
then you get the concentration, and then just do the K expression, and voila 3.41