Direction of reaction when Q<K and Q>K

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Jennifer1E
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Joined: Fri Jun 23, 2017 11:39 am

Direction of reaction when Q<K and Q>K

Postby Jennifer1E » Sun Jul 23, 2017 9:05 pm

How can we tell what direction does the reaction favor when Q<K and Q>K?

Chem_Mod
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Re: Direction of reaction when Q<K and Q>K

Postby Chem_Mod » Sun Jul 23, 2017 10:53 pm

Q<K : products are favored
Q>K : reactants are favored

FCervania 1B
Posts: 14
Joined: Wed Jun 28, 2017 3:00 am

Re: Direction of reaction when Q<K and Q>K

Postby FCervania 1B » Sun Jul 30, 2017 5:51 am

Any easy way to remember this is always think of their order in the alphabet!
P Q R
if we say
P= product
R= reactant
and Q is to be replaced with an arrow, we get 2 options.

**Make sure you compare as Q (either < or >) K, not K (< or >) Q, or this tip won't work!**

If Q > K, then the inequality sign is pointing RIGHT, so replace the Q with an arrow -->
we get: P --> R
We see that it is pointing towards R

If Q < K , then the inequality sign is pointing LEFT, so replace the Q with arrow <--
we get: P <-- R
We see that it is pointing towards P

Really simple to remember, hope this helped!


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