ignoring x validity

marcus lin 1E
Posts: 54
Joined: Fri Sep 28, 2018 12:28 am

ignoring x validity

so if we ignore x and it isn't less than 5% of the original molarity and is therefore invalid, do we just continue to calculate x quadratically?

BenJohnson1H
Posts: 68
Joined: Fri Sep 28, 2018 12:17 am

Re: ignoring x validity

precisely, unless it is a cubic in which you would have three possible values of X. Then plug the values in to see which value is viable

chaggard
Posts: 37
Joined: Fri Sep 28, 2018 12:19 am

Re: ignoring x validity

Yes, because anything over 5% alters the value for x. So your answer would be slightly off.

Xingzheng Sun 2K
Posts: 62
Joined: Fri Sep 28, 2018 12:29 am

Re: ignoring x validity

That is what we are supposed to do. The formula to calculate x is given on the formula sheet, and it always works for solving the x.

Kavvya Gupta 1H
Posts: 35
Joined: Fri Sep 28, 2018 12:21 am

Re: ignoring x validity

you only ignore the x generally when x<10^-3. Usually, x will be less than 5%, but if it isn't then you would do quadratic as your answer would be slightly off otherwise.

taryn_baldus2E
Posts: 62
Joined: Fri Sep 28, 2018 12:24 am

Re: ignoring x validity

You can also check to see if it was okay to make this approximation by calculating the value for x by the original concentration and multiplying by 100 to see if it was truly less than 5%.

Shibhon_Shepard
Posts: 62
Joined: Wed Nov 15, 2017 3:04 am

Re: ignoring x validity

But are they going to give us a problem that is x^3?