Empirical Ratio Rounding

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Kyla Grunden 1L
Posts: 46
Joined: Sat Sep 07, 2019 12:16 am

Empirical Ratio Rounding

Postby Kyla Grunden 1L » Sun Oct 06, 2019 9:16 pm

Several times I have seen that, when you divide by the smallest molar mass when trying to find the empirical formula, the ratios are not always whole numbers. At what point is it too far to round to find the ratio?

Sean1F
Posts: 19
Joined: Sat Sep 07, 2019 12:16 am

Re: Empirical Ratio Rounding

Postby Sean1F » Sun Oct 06, 2019 9:20 pm

As I've said in a previous reply to another post, I would say that you should round if the decimal is .1 or .2. Anything larger would lead to inaccurate results because a false ratio. Thanks for posting this! :D

Ami_Pant_4G
Posts: 106
Joined: Sat Aug 24, 2019 12:17 am

Re: Empirical Ratio Rounding

Postby Ami_Pant_4G » Sun Oct 06, 2019 10:30 pm

Also, I think if there is anything ending with .9 after dividing, it is okay to round up. Hope this helps!

Sean Tran 2K
Posts: 65
Joined: Sat Aug 17, 2019 12:17 am

Re: Empirical Ratio Rounding

Postby Sean Tran 2K » Sun Oct 06, 2019 10:37 pm

As Ami mentioned, .9 would be okay to round up for figuring out empirical formulas, but what if it is .8?

EricZhao3G
Posts: 51
Joined: Tue Oct 08, 2019 12:16 am

Re: Empirical Ratio Rounding

Postby EricZhao3G » Wed Oct 09, 2019 1:52 pm

If it is 0.8, I believe you would have to multiply all of the elements of the compound by 5 in order to find the empirical formula since that is the smallest number you can multiply by to get a whole number. Rounding 0.8 to 1 is a bit of a stretch even if you rounded in your work.

Kishan Shah 2G
Posts: 132
Joined: Thu Jul 11, 2019 12:15 am

Re: Empirical Ratio Rounding

Postby Kishan Shah 2G » Wed Oct 09, 2019 2:00 pm

Usually you will intuitively know if the number is able to be rounded to a whole number or not. Usually my values that I round accurately to a whole number are within .05 of the whole number. If they are not whole numbers, in which it can happen, write the empirical formula down with the decimal subscript and find a number to multiple it by so you can get a whole number. Then multiply the other subscripts by this number as well.

Juana Abana 1G
Posts: 100
Joined: Wed Sep 18, 2019 12:15 am

Re: Empirical Ratio Rounding

Postby Juana Abana 1G » Fri Oct 11, 2019 8:34 am

I think if after dividing you get .9 then it is okay to round up in order to get the empirical formula.


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