Sig Figs [ENDORSED]
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Re: Sig Figs
Write it in scientific notation (10^-4), then look at the number of figures. Leading zeroes are not considered significant, so you'll count your nonzero integers for this problem.
Re: Sig Figs
If a number is written in scientific notation with a zero, for example 5.60*10^4, then does only the one 0 count as significant or would it have 3 significant zeros because of the 10^4?
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Re: Sig Figs
Your example would only have 3 sig figs. In order for that number to have 3 significant zeros, it would have to be written as 5.6000*10^4. Hopefully this helped.
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Re: Sig Figs
When using the mass of an element to solve for a problem would it be best to use the complete mass given in the periodic table or round? For instance, (N) has a mass of 14.007, would my final answer be thrown off if I were to round and use 14.01?
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Re: Sig Figs
I think that the problems are computed using whichever values are in the given periodic table. So if your periodic table says 14.007, the answer key probably uses that value to find their final answer. This means that if you were to round, you might end up with a slightly different value for the last significant digit, but your whole number won't be off by much, so the grader will probably excuse the discrepancy. However, I would just use the values given in the table you are provided for a particular problem because it can't hurt you to be as close to the answer key as possible :)
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Re: Sig Figs
Hello!
I just wanted to ask if the 0 after the number 0.0450 counts as a significant figure? Is this 5 or 4 sig figs?
I just wanted to ask if the 0 after the number 0.0450 counts as a significant figure? Is this 5 or 4 sig figs?
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Re: Sig Figs
There are 3 sig figs in 0.0450. This is more clearly shown if you write it in scientific notation as 4.50 x 10^-2
The 0s before 450 do not count as sig figs.
The 0s before 450 do not count as sig figs.
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Re: Sig Figs
There are 3 sig figs. The 0's to the left of nonzero numbers do not count as sig figs. However, if there were 0's to the right of nonzero numbers, those 0's would be significant.
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Re: Sig Figs
I think that the rule of final and trailing zeros are what poses the most challenge to me. Thank you for all the clarifications regarding rules of zeros. It was definitely helpful.
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Re: Sig Figs
These are the general rules for sig figs as explained to me by an undergraduate assistant:
All non 0s are significant.
There are three types of zeros:
(a) leading 0s (in beginning) are NEVER significant [i.e., 0.0567 --> 3 Sig Figs]
(b) trapped 0s (in middle) are ALWAYS significant [i.e., 2018 --> 4 Sig Figs]
(c) trailing 0s (last) are maybe significant
- if decimal point exists anywhere, 0 is significant [i.e., 300. --> 3 Sig Figs]
- if no decimal, 0 is not significant [i.e., 300 --> 1 Sig Fig]
All non 0s are significant.
There are three types of zeros:
(a) leading 0s (in beginning) are NEVER significant [i.e., 0.0567 --> 3 Sig Figs]
(b) trapped 0s (in middle) are ALWAYS significant [i.e., 2018 --> 4 Sig Figs]
(c) trailing 0s (last) are maybe significant
- if decimal point exists anywhere, 0 is significant [i.e., 300. --> 3 Sig Figs]
- if no decimal, 0 is not significant [i.e., 300 --> 1 Sig Fig]
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