Sig Figs  [ENDORSED]

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Grace_McAuley_1E
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Sig Figs

Postby Grace_McAuley_1E » Sun Oct 09, 2016 10:38 pm

How many significant figures are in 0.000234?

Alexander Chen 3N
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Re: Sig Figs  [ENDORSED]

Postby Alexander Chen 3N » Sun Oct 09, 2016 10:53 pm

3

This can be seen more easily if you convert this to scientific notation.

Gianna Zufall 3G
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Re: Sig Figs

Postby Gianna Zufall 3G » Mon Oct 10, 2016 8:33 pm

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.

Grace_McAuley_1E
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Re: Sig Figs

Postby Grace_McAuley_1E » Thu Oct 13, 2016 11:35 am

Thank you!

veeksha25
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Re: Sig Figs

Postby veeksha25 » Sat Oct 22, 2016 7:42 pm

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?

Adam Wojnar 1K
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Joined: Wed Sep 21, 2016 2:56 pm

Re: Sig Figs

Postby Adam Wojnar 1K » Sat Oct 22, 2016 11:27 pm

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.

Sarahi Cota-Felix 1C
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Re: Sig Figs

Postby Sarahi Cota-Felix 1C » Sun Jul 02, 2017 10:19 am

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?

Isita Tripathi 2E
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Re: Sig Figs

Postby Isita Tripathi 2E » Thu Oct 05, 2017 3:46 pm

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 :)

Michael Cheng 1C
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Joined: Thu Jul 13, 2017 3:00 am

Re: Sig Figs

Postby Michael Cheng 1C » Thu Oct 05, 2017 7:52 pm

How many sig figs is in 0.053?

Lorie Seuylemezian-2K
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Re: Sig Figs

Postby Lorie Seuylemezian-2K » Thu Oct 05, 2017 7:53 pm

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?

Evelyn L 1H
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Joined: Fri Sep 29, 2017 7:05 am

Re: Sig Figs

Postby Evelyn L 1H » Thu Oct 05, 2017 8:13 pm

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.

Angel Ni 2K
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Joined: Sat Jul 22, 2017 3:01 am

Re: Sig Figs

Postby Angel Ni 2K » Fri Oct 06, 2017 11:22 am

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.

Tatiana Hage 2E
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Re: Sig Figs

Postby Tatiana Hage 2E » Fri Oct 06, 2017 12:51 pm

There are 2 sig figs in 0.053 since the 0's before 53 do not count.

Amy Zheng 2l
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Re: Sig Figs

Postby Amy Zheng 2l » Fri Oct 06, 2017 12:59 pm

3 significant figures

juliensantosdis3g
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Joined: Fri Sep 29, 2017 7:06 am

Re: Sig Figs

Postby juliensantosdis3g » Sat Oct 07, 2017 11:08 pm

It is 3 sig figs

Anna Lapuos 3C
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Re: Sig Figs

Postby Anna Lapuos 3C » Sat Oct 07, 2017 11:22 pm

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.

Jada Larson 1F
Posts: 31
Joined: Fri Apr 06, 2018 11:03 am

Re: Sig Figs

Postby Jada Larson 1F » Sun Apr 15, 2018 9:44 pm

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]


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