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Quadratic

Posted: Thu Jan 16, 2020 9:53 am
by 605110118
What do you do if the after using the quadratic equation and you get two positive answers?

Re: Quadratic

Posted: Thu Jan 16, 2020 11:22 am
by Morgan Carrington 2H
You would test each value with the equilibrium expression that was found using the ICE table to see if the value is reasonable. Usually one of the values found using the quadratic equation will cause one of the concentrations to be negative, which is not possible.

Re: Quadratic

Posted: Thu Jan 16, 2020 11:24 am
by BritneyP- 2c
You should test each value, and rule out the one that is unreasonable in the situation. Usually you will end up with a positive and negative number, so it can immediately rule out.

Re: Quadratic

Posted: Thu Jan 16, 2020 11:27 am
by Sally Qiu 2E
i don't think you would get 2 positive answers often, but just in case i'd plug the values back into the ICE table to see which value is more reasonable

Re: Quadratic

Posted: Thu Jan 16, 2020 11:28 am
by Max Madrzyk Dis 4G
I think the chances that you would get two positive values after using the quadratic equation are pretty low but if you do I would plug them back into the ICE table and see which value is more reasonable.

Re: Quadratic

Posted: Thu Jan 16, 2020 11:48 am
by Betania Hernandez 2E
If you get two positive answers, you could rule out the value that is greater than your initial concentration since it would result in a negative number when plugged in to the equilibrium expression.

Re: Quadratic

Posted: Thu Jan 16, 2020 4:55 pm
by Ruby Richter 2L
If you do the quadratic equation and get a positive and negative number would you just discredit the negative number? Why?

Re: Quadratic

Posted: Fri Jan 17, 2020 11:56 am
by CynthiaLy4F
If you use the quadratic formula and get two positive answers, you would choose the answer where if you subtract it from any of the initial conditions given it would be result in a reasonable and nonnegative concentration or pressure.

Re: Quadratic

Posted: Fri Jan 17, 2020 4:38 pm
by 705121606
You would use the number that is less than your initial concentration you were given in the original problem.

Re: Quadratic

Posted: Fri Jan 17, 2020 5:02 pm
by 805373590
You will test out the two answers and the answer that is less than the initial answer will be the correct one

Re: Quadratic

Posted: Fri Jan 17, 2020 5:12 pm
by Amanda Mei 1B
Ruby Richter 2L wrote:If you do the quadratic equation and get a positive and negative number would you just discredit the negative number? Why?


Because you can't have a negative concentration