## Quadratic Equations from ICE Box [ENDORSED]

Jasmine Wu 1L
Posts: 55
Joined: Thu Jul 27, 2017 3:00 am
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### Quadratic Equations from ICE Box

When you solve for x after completing the ICE box and setting up the quadratic equation, I noticed that sometimes you could get two positive answers. How would you choose which solution for x is relevant to the question and answer? I know for the solutions with one positive and one negative answer, you would choose the positive one. But what if there were two positives?

Thanks!

Aijun Zhang 1D
Posts: 53
Joined: Tue Oct 10, 2017 7:13 am

### Re: Quadratic Equations from ICE Box

You should choose the answer that is smaller than the initial concentration of the reactants.
Because x is just an amount of change during the reaction, so the concentration change must be smaller than the initial concentration of reactants. If it is larger, then the answer should be rejected.

AtreyiMitra2L
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### Re: Quadratic Equations from ICE Box  [ENDORSED]

When you get 2 positive answers, you take the value that would give you equilibrium concentrations that are lower than the initial concentrations.