In a 1.00 L flask, 0.72 mol of PCl5 and 0.18 mol ofPCl3 are mixed together. Reaction occurrred to equilibrium and tests showed that 0.60 mol of PCl5 was now present. Calculate the Keq value.
(Answer: 6.0*10-2)although I cannot figure out how to find this without a given value from Cl2.
8 years ago
Answered By Charles S
This is a great question! Take a look at the wording "reaction occured to equilibrium" and "mixed together" or "placed in a container". This is a sure way of knowing that an ICE table may be required. First step is to set up the ice table and set the initial values to 0.72 and 0.18. It doesn't give you the Cl2 but you can assume that it is zero. Now you can find the change using the final equilibrium amount of PCl5. Check out the whiteboard for the full solution! Also, don't forget that the reactant had to be subtract and the products were addition. Also, the change is proportional to the mole ratio. It is a 1:1:1 ratio. Check out http://www.tutortag.com/calgary/subjects/chemistry30/equilibrium-ice-table-3 for a full video on ICE tables.
8 years ago
Answered By Charles S
This is a great question! Take a look at the wording "reaction occured to equilibrium" and "mixed together" or "placed in a container". This is a sure way of knowing that an ICE table may be required. First step is to set up the ice table and set the initial values to 0.72 and 0.18. It doesn't give you the Cl2 but you can assume that it is zero. Now you can find the change using the final equilibrium amount of PCl5. Check out the whiteboard for the full solution! Also, don't forget that the reactant had to be subtract and the products were addition. Also, the change is proportional to the mole ratio. It is a 1:1:1 ratio. Check out http://www.tutortag.com/calgary/subjects/chemistry30/equilibrium-ice-table-3 for a full video on ICE tables.
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