sig figs
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Re: sig figs
The best measure of how many sig figs to use is to look in the question provided and use the smallest amount, it also helps to try and keep the number of sig figs consistent for all measurements.
Re: sig figs
Yes as the previous post mentioned you want to round off your number of significant figures to the same amount of sig figs that the question has :)
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Re: sig figs
You should round off only at the very end and keep everything in the intermediate calculations(or keep, like, 2 extra decimal places, I guess).
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Re: sig figs
If there are zeros before the sig figs (like 0.0001), then all of the zeros are significant. If the number is an integer like 10, the zero is significant because there are no decimals. If it were 10.0, the last zero would not be considered to be significant unless specified by the question. If the number was like 0.100, neither of the zeros after the one would be significant.
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Re: sig figs
you should use exact values from the periodic table and avoid rounding or using sig figs until the very end. this will minimize rounding error :)
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Re: sig figs
How do I tell what 0's are significant and which aren't?
If you want to practice determining how many significant figures a number has, this could be helpful:
https://www.khanacademy.org/math/arithmetic-home/arith-review-decimals/arithmetic-significant-figures-tutorial/e/significant_figures_1
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Re: sig figs
Some rules for significant figures: non zero numbers are always significant, any zero between 2 non zero numbers are significant, and trailing zeros after a decimal point are significant.
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Re: sig figs
This is what I got from Appendix 1 (1C) in the textbook:
-Addition and Subtraction: round to the lowest number of sig figs after the decimal
-Multiplication and Division: round to the lowest number of sig figs in general
-Zeros between nonzero numbers (ex. 30.1): significant
-Zeros after the decimal (ex. 3.0): significant because they are measured
-Zeros before sig figs that are less than 1 (ex. 0.005): insignificant because they are just placeholders.
-Zeros after a whole number (ex. 100): ambiguous, can be considered as having only 1 sig fig unless there is a decimal (100. has 3 sig figs) or there is scientific notation (1.00 x 10^2 has 3 sig figs).
-Addition and Subtraction: round to the lowest number of sig figs after the decimal
-Multiplication and Division: round to the lowest number of sig figs in general
-Zeros between nonzero numbers (ex. 30.1): significant
-Zeros after the decimal (ex. 3.0): significant because they are measured
-Zeros before sig figs that are less than 1 (ex. 0.005): insignificant because they are just placeholders.
-Zeros after a whole number (ex. 100): ambiguous, can be considered as having only 1 sig fig unless there is a decimal (100. has 3 sig figs) or there is scientific notation (1.00 x 10^2 has 3 sig figs).
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Re: sig figs
After reading these posts I am confused about whether or not a zero is considered a sig fig if there is a number like 13.0
Since the zero is trailing the decimal point would it or would it not be a sig fig when doing arithmetic calculations?
Since the zero is trailing the decimal point would it or would it not be a sig fig when doing arithmetic calculations?
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Re: sig figs
Will we be marked down on an exam for using the incorrect amount of sig figs in our answer?
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Re: sig figs
Maya Serota 3G wrote:After reading these posts I am confused about whether or not a zero is considered a sig fig if there is a number like 13.0
Since the zero is trailing the decimal point would it or would it not be a sig fig when doing arithmetic calculations?
In the example you gave (13.0), the 0 would be considered a sig fig when doing arithmetic calculations because it comes after the decimal point.
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Re: sig figs
Also, do not worry too much as sig figs are not vital to test 1. Try your best but sig figs do not need to be absolutely mastered to score well on test 1
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Re: sig figs
Zeros are not considered a sig fig if it is in front of a decimal. For example, 0.245. Since the zero is in front of the decimal, it would not be counted as a sig fig. So in response the sig fig would be three. If it is still confusing, the link below explains it better than I do.
https://youtu.be/IIQPHC5gZT8
https://youtu.be/IIQPHC5gZT8
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Re: sig figs
Kehlin Hayes 4C wrote:The best measure of how many sig figs to use is to look in the question provided and use the smallest amount, it also helps to try and keep the number of sig figs consistent for all measurements.
This is generally a great practice, however, there are slightly different sig fig rules for addition/subtraction versus multiplication/division.
Check out page 6 and 7 of this link for more info http://tournas.rice.edu/website/documen ... Rules1.pdf
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Re: sig figs
Kimme Chun 1I wrote:How do I tell what 0's are significant and which aren't?
Here's a link with a good trick for remembering which 0's are significant. https://www.kentchemistry.com/links/Mea ... igfigs.htm
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Re: sig figs
Adding/Subtracting --> round to the least precise # (i.e. 4.23+4.542 = ? ; Your answer should have 2 decimal points)
v.
Mutiplying/Dividing --> # of sig figs in answer = least # of sig figs in whatever you're multiplying (i.e. 4.0*2 =8)
v.
Mutiplying/Dividing --> # of sig figs in answer = least # of sig figs in whatever you're multiplying (i.e. 4.0*2 =8)
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Re: sig figs
Does anyone know if points will be taken off due to sig figs? My high school chem teacher was super specific on SFs.
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Re: sig figs
When doing the actual work for the problem, don't round off and try to keep intermediate answers 3-4 decimal places. However, at the very end, you want to round off based on the lowest number of sig figs. If you don't know the rules for sig figs, I'd suggest you to look at Professor Lavelle's website link called, "Everything you want to know about Sig Fig"
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