Q on Top Score G-Chem test #1 Q 56 of 30

solution explains it really well.... we are given moles & volume, hence we can figure out molarity (M) = moles/L = 14.250/3 = 4.75 right?

Now the question says only 40% of PCL5 decomposes...which means only 4.75M x 40% = 1.9 M reacted. So we are left with 4.75-1.9 = 2.85M of PCl5.

Since the equation is balance..and the mole ratio is 1:1...we will obtain 1.9 of PCl3 & Cl2
Kc = [PCl3][Cl2]/[PCl5]
= (1.9)(1.9)/(2.85)
= (1.9)^2/(2.85)

ahhh, my brain is fried and nothing makes sense. i need a break. thanks for the help!!

np