Significant Figures In A Given Weight
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Significant Figures In A Given Weight
If it is given that there are 7 grams of a substance in a mole of that, would you use the one significant figure in the given value to formulate how many significant figure the final answer would be after calculation?
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Re: Significant Figures In A Given Weight
I believe that since 7 is an integer, it should not affect the significant figures in your calculation. Integers and exact numbers do not affect sf. You would most likely be given an inexact measurement that could be used as the least number of significant figure to determine your answer.
Take a look at the following resources for more detailed information:
https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf
https://lavelle.chem.ucla.edu/wp-conten ... ussion.pdf
Take a look at the following resources for more detailed information:
https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf
https://lavelle.chem.ucla.edu/wp-conten ... ussion.pdf
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Re: Significant Figures In A Given Weight
Hi! I think if the question states "7" then it has one significant figure only. Also, numbers like 70, 700, and 7,000 all have only one significant figure because I think there is a rule that states "the last zeros of an integer number do not count as significant numbers".
Hope it helps! :)
Hope it helps! :)
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Re: Significant Figures In A Given Weight
Hi! I think "7" has one sig fig, and if the 7 gram is used in the calculation, it does limit the sig fig to one.
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Re: Significant Figures In A Given Weight
Hi! I believe you would only use one significant figure when giving your answer because when multiplying/dividing, the value with the least significant figures determines the number of significant figures in the answer and 1 sig fig is the least amount of sig figs you can have. The Everything you want to know about Significant Figures on Dr. Lavelle's website really helped!
Hope this was useful.
Hope this was useful.
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Re: Significant Figures In A Given Weight
Make sure that you acknowledge exactly what the "7" is listed as in the problem. If it just says 7, then that's one significant figure, but if it says 7.00 that would be three significant figures. Hope this helps!
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Re: Significant Figures In A Given Weight
I was also confused as to whether we would consider a one-digit integer that is given in the problem to affect the number of significant figures. However, even though it's an integer, it's still not an exact, known number (I believe) and since this is the case you have to write your final answer with just one significant figure, like everyone else said. I'm still uncertain, but I think this is the reason why a value like "7 grams" would in fact affect the number of sig figs.
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Re: Significant Figures In A Given Weight
In this case, if it is given as "7" then you should use only one significant figure in your answer! In the case of "7.0", 2 sig figs, or "7.00", 3 sig figs, then there would be 2 sig figs or 3 sig figs in your answer. As long as you use as many sig figs as there were given in the problem, then your answer would just contain the same amount of sig figs.
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Re: Significant Figures In A Given Weight
For that question I believe that since 7 is an integer, there is no specific amount of significant figures that you should use. I would suggest using only 1 anyway since there are no zeros after the integer, just to be safe. Usually for questions involving moles and grams, you should use the least number of significant figures that are given in the question. For instance, if the question gives you 1.7 g and 0.115 M (or something otherwise), use only 2 significant figures since 1.7 only has 2. Hope this helps!
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Re: Significant Figures In A Given Weight
For anyone having trouble with significant figures, the following link is what I use if I ever get confused.
https://getstartedinscience.weebly.com/ ... orig.jpg?1
This summarizes the rules of significant figures pretty well :)
https://getstartedinscience.weebly.com/ ... orig.jpg?1
This summarizes the rules of significant figures pretty well :)
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Re: Significant Figures In A Given Weight
Jay Solanki 3E wrote:For that question I believe that since 7 is an integer, there is no specific amount of significant figures that you should use. I would suggest using only 1 anyway since there are no zeros after the integer, just to be safe. Usually for questions involving moles and grams, you should use the least number of significant figures that are given in the question. For instance, if the question gives you 1.7 g and 0.115 M (or something otherwise), use only 2 significant figures since 1.7 only has 2. Hope this helps!
So if any number is an integer, it doesn't count for significant figures? I thought the difference was whether it was a measurement or a given value. In this case, since it's 7 grams (a measurement specific to the problem), wouldn't it just be 1 significant figure as Cecilia said?
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Re: Significant Figures In A Given Weight
I read that "exact numbers, such as integers, are treated as if they have an infinite number of significant figures," and so you dont need to look at integers for determining sig figs.
Heres the link I used:http://www.chemistry.wustl.edu/~coursedev/Online%20tutorials/SigFigs.htm#:~:text=Rules%20for%20Using%20Significant%20Figures&text=Exact%20numbers%2C%20such%20as%20integers,if%20it%20is%20below%205.
Heres the link I used:http://www.chemistry.wustl.edu/~coursedev/Online%20tutorials/SigFigs.htm#:~:text=Rules%20for%20Using%20Significant%20Figures&text=Exact%20numbers%2C%20such%20as%20integers,if%20it%20is%20below%205.
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