Empirical Formula  Whole Number Ratio
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Empirical Formula  Whole Number Ratio
I was wondering what the cutoff for rounding the moles to a whole number is. I am assuming if its less than .10 away you can round it to the nearest number?

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Re: Empirical Formula  Whole Number Ratio
I don't think there is a literal cutoff for rounding. In most cases, it should be fairly obvious whether or not the number should be rounded up or not, as the numbers are usually less than 0.2 away from a whole number. Just go with your gut and you'll be fine.

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Re: Empirical Formula  Whole Number Ratio
I do not think there is a set value. Usually round to the nearest whole number if it is like less than .10 away. If it is more, then try multiplying it by integers until you get a whole number.

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Re: Empirical Formula  Whole Number Ratio
There isn't really a setinstone cut off value for rounding moles to a whole number. But, in some of the UA sessions I've attended, they said to just use your logic in rounding and typically round down or up is the value is less than 0.1 or greater than 0.9. Hope this helps!

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Re: Empirical Formula  Whole Number Ratio
I don't think that there is a set value to round to the nearest whole number. However if you see that it is a rather large difference (like 4/3 or 3/2), then I would try multiplying the ratios until you get a whole number for each atom. Hope this helped!

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Re: Empirical Formula  Whole Number Ratio
Hi! Agreeing with everyone above, just go with your gut feeling for rounding. If you have to multiply by an extremely large number for it to work out or you feel like something is off, you can always check your previous calculations as well to be sure nothing went wrong there. Generally, I aim for less than .20 away from the whole number before rounding.

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Re: Empirical Formula  Whole Number Ratio
Stacey Phan 3I wrote:I was wondering what the cutoff for rounding the moles to a whole number is. I am assuming if its less than .10 away you can round it to the nearest number?
Hi! I would say in general if it is near about .1 then it is ok to consider that it is a whole number. I think that in our class it will be obvious if we need to multiply by another number. By that I mean that we would probably get something like 1.333 (multiply by three) or 2.5 (multiply by 2) where it would be clear. Hope this helps!

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 Joined: Wed Sep 30, 2020 9:44 pm
Re: Empirical Formula  Whole Number Ratio
No, there isn't really a specific cutoff for empirical formulas. I think in most cases if you do the steps right you should be able to get a pretty good ratio. I wouldn't worry too much about it.

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 Joined: Wed Sep 30, 2020 9:35 pm
Re: Empirical Formula  Whole Number Ratio
I think with the questions that we're asked in this course, the rounding should be pretty clear if all the steps were right. With the practice we've had so far with the Sapling hw and the textbook questions, most of the decimals came out to be values like .98 or .002 (things that make it clear where the rounding should be).

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 Joined: Wed Sep 30, 2020 10:03 pm
Re: Empirical Formula  Whole Number Ratio
I do not think that there is a cutoff for rounding, especially since the numbers just tend to be very close to round. There would be "cutoffs" for when we should round, such as having _.33 and then multiplying by 3 to get the closest number.
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