Quadratic

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605110118
Posts: 75
Joined: Wed Sep 18, 2019 12:21 am

Quadratic

Postby 605110118 » Thu Jan 16, 2020 9:53 am

What do you do if the after using the quadratic equation and you get two positive answers?

Morgan Carrington 2H
Posts: 54
Joined: Wed Nov 14, 2018 12:22 am

Re: Quadratic

Postby Morgan Carrington 2H » Thu Jan 16, 2020 11:22 am

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.

BritneyP- 2c
Posts: 101
Joined: Sat Sep 14, 2019 12:15 am

Re: Quadratic

Postby BritneyP- 2c » Thu Jan 16, 2020 11:24 am

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.

Sally Qiu 2E
Posts: 105
Joined: Fri Aug 30, 2019 12:18 am

Re: Quadratic

Postby Sally Qiu 2E » Thu Jan 16, 2020 11:27 am

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

Max Madrzyk Dis 4G
Posts: 102
Joined: Wed Sep 18, 2019 12:21 am

Re: Quadratic

Postby Max Madrzyk Dis 4G » Thu Jan 16, 2020 11:28 am

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.

Betania Hernandez 2E
Posts: 107
Joined: Fri Aug 02, 2019 12:15 am

Re: Quadratic

Postby Betania Hernandez 2E » Thu Jan 16, 2020 11:48 am

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.

Ruby Richter 2L
Posts: 103
Joined: Thu Jul 25, 2019 12:17 am

Re: Quadratic

Postby Ruby Richter 2L » Thu Jan 16, 2020 4:55 pm

If you do the quadratic equation and get a positive and negative number would you just discredit the negative number? Why?

CynthiaLy4F
Posts: 103
Joined: Sat Jul 20, 2019 12:16 am

Re: Quadratic

Postby CynthiaLy4F » Fri Jan 17, 2020 11:56 am

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.

705121606
Posts: 68
Joined: Wed Sep 18, 2019 12:17 am

Re: Quadratic

Postby 705121606 » Fri Jan 17, 2020 4:38 pm

You would use the number that is less than your initial concentration you were given in the original problem.

805373590
Posts: 101
Joined: Wed Sep 11, 2019 12:17 am

Re: Quadratic

Postby 805373590 » Fri Jan 17, 2020 5:02 pm

You will test out the two answers and the answer that is less than the initial answer will be the correct one

Amanda Mei 1B
Posts: 109
Joined: Sat Aug 24, 2019 12:16 am

Re: Quadratic

Postby Amanda Mei 1B » Fri Jan 17, 2020 5:12 pm

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


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