Assuming X value

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Sophia_Kiessling_2L
Posts: 61
Joined: Fri Sep 28, 2018 12:26 am

Assuming X value

Postby Sophia_Kiessling_2L » Sun Jan 20, 2019 11:59 am

How small does the Kb/Ka value have to be in order to assume the value of X and not have to use the quadratic formula?

Jenna Salas 2H
Posts: 30
Joined: Fri Sep 28, 2018 12:22 am

Re: Assuming X value

Postby Jenna Salas 2H » Sun Jan 20, 2019 12:04 pm

The Ka or Kb should be less than 10^-3 in order to assume the value of x doesn't have to be used. However, you should always check to see if your approximation is okay. Your approximation is okay if it's less than 5% of the initial value.

JT Wechsler 2B
Posts: 62
Joined: Fri Sep 28, 2018 12:16 am

Re: Assuming X value

Postby JT Wechsler 2B » Sun Jan 20, 2019 12:24 pm

The Ka or KB should be less than 10^-3 in a reaction just to be safe and apply the 5% approximation.

eden tefera 2B
Posts: 39
Joined: Fri Sep 28, 2018 12:21 am

Re: Assuming X value

Postby eden tefera 2B » Sun Jan 20, 2019 3:35 pm

You can typically assume that the value of x is negligible when the Ka or Kb is less that 10^-3. If it's not, then you should always include x in your calculations.


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