View Full Version : topscore question please..


GRAD
08-28-2006, 10:06 PM
WHen 14.250 moles of PCl5 gas is placed in a 3 L container and comes to equilibrium at a constant temp, 40% of the PCl5 decomposes according to the following equation:

PCL5 ----> PCl3 + Cl2

What is Kc?

fancymylotus
08-28-2006, 10:10 PM
WHen 14.250 moles of PCl5 gas is placed in a 3 L container and comes to equilibrium at a constant temp, 40% of the PCl5 decomposes according to the following equation:

PCL5 ----> PCl3 + Cl2

What is Kc?


I HATE CHEM:barf:

GRAD
08-29-2006, 11:06 AM
anyone?

allstardentist
08-29-2006, 11:17 AM
i dont have topscore wit me at this moment, but i think it's like this:

# moles of Cl2 = PCl3 = .4(14.25)
# moles of PCl5 = .6(14.25)

To get the conc. of each one, divide them by 3 since the volume is 3L.

so Kc= (.4(14.25/3))^2/(.6*14.25/3)

I remember topscore actually multilplied out .4 *14.25/3 and .6*14.25/3

lifeisgood
08-29-2006, 11:27 AM
i dont have topscore wit me at this moment, but i think it's like this:

# moles of Cl2 = PCl3 = .4(14.25)
# moles of PCl5 = .6(14.25)

To get the conc. of each one, divide them by 3 since the volume is 3L.

so Kc= (.4(14.25/3))^2/(.6*14.25/3)

I remember topscore actually multilplied out .4 *14.25/3 and .6*14.25/3

looks right to me