- Joined
- Jun 14, 2005
- Messages
- 1,000
- Reaction score
- 3
Hey guys, here are a couple of gchem questions i cant seem to figure out. if anyone can help me, that would be great. thanx in advance:
1) if the activiation energy for a reaction in the forward direction is 96kJ, the activation energy for the reaction in reverse is 295 kj, and the energy of the products is 34kj, the energy of the reactants is?
a) - 233kj/mole
b) 233 kJ/mole
c) -199 kJ/mole
d) 199 kJ/mole
e) -34 kj/mole
answer: B
2) When 14.250 moles of PCL5 gas is placed in a 3 liter container and comes to equilibrium at constant temperature, 40% of the PCL5 decomposes according to the equation:
PCl5 (g) <-> PCL3 (g) + Cl2(g)
what is the value of Kc for this reaction?
a) (1.896)^2/2.854
b) (2.854)^2/1.898
c) (3.8)^2/2.854
d) (2.854)(1.896)/3.8
e) none of the above
answer: A
I picked (e) bc the molarity of PCL5 is 4.75m/l, and 40% of that is 1.896 which is the concentration of PCL3 and CL2. thus, when i put it into the equilibrium equ: Kc=(1.896)^2/4.75. this answer resembles that of A, but for some reason the denominator was divded in half. anyone know why?
1) if the activiation energy for a reaction in the forward direction is 96kJ, the activation energy for the reaction in reverse is 295 kj, and the energy of the products is 34kj, the energy of the reactants is?
a) - 233kj/mole
b) 233 kJ/mole
c) -199 kJ/mole
d) 199 kJ/mole
e) -34 kj/mole
answer: B
2) When 14.250 moles of PCL5 gas is placed in a 3 liter container and comes to equilibrium at constant temperature, 40% of the PCL5 decomposes according to the equation:
PCl5 (g) <-> PCL3 (g) + Cl2(g)
what is the value of Kc for this reaction?
a) (1.896)^2/2.854
b) (2.854)^2/1.898
c) (3.8)^2/2.854
d) (2.854)(1.896)/3.8
e) none of the above
answer: A
I picked (e) bc the molarity of PCL5 is 4.75m/l, and 40% of that is 1.896 which is the concentration of PCL3 and CL2. thus, when i put it into the equilibrium equ: Kc=(1.896)^2/4.75. this answer resembles that of A, but for some reason the denominator was divded in half. anyone know why?