All students read this sig fig post  [ENDORSED]

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Rida Ismail 1H
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Joined: Sat Sep 07, 2019 12:16 am

Re: All students read this sig fig post

Postby Rida Ismail 1H » Thu Oct 03, 2019 10:12 pm

Evamae Bayudan 1B wrote:Will we be penalized for putting extra significant figures?


Yes, I believe we will because sig figs determine the amount of precision that a number contains. If we have too many or too few sig figs, our precision for that number will be off

ZevMarx-Kahn3C
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Re: All students read this sig fig post

Postby ZevMarx-Kahn3C » Fri Oct 04, 2019 1:05 am

How do you deal with significant figures when you have exact values (e.g., exactly 1:2 ratio of molecules in a reaction)? Do we treat the exact value as having infinite sig figs?

Emma Joy Schaetz 1E
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Re: All students read this sig fig post

Postby Emma Joy Schaetz 1E » Fri Oct 04, 2019 9:06 am

JasmineChavez 1E wrote:
Samantha Rundle 4L wrote:Are we supposed to have the correct sig figs for each step or just the final answer?

Thanks!



Only the final answer requires the correct number of significant figures but for quizzes there are only a certain amount of points you can lose for significant figures. In others words you do not lose a point every time your sig figs are incorrect on an answer. I was told by a TA there are only so many points awarded for this and it is better to understand the concepts and calculations and then implement your sig fig knowledge


Is this also true for exams? Or will the midterm and final take off more points for sig figs?

Justin Quan 3B
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Re: All students read this sig fig post

Postby Justin Quan 3B » Fri Oct 04, 2019 10:23 am

When showing work on homework, must we write out all the sig figs in the intermediate steps even when we know the final answer will have fewer sig figs?

Nathan Rothschild_3D
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Re: All students read this sig fig post

Postby Nathan Rothschild_3D » Fri Oct 04, 2019 10:52 am

Also don't forget any equations or constants that you are using to convert g to mols or anything else should not be taken into account for when figuring how many sig figs your answer should be in.

Nathan Rothschild_3D
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Joined: Fri Aug 02, 2019 12:15 am

Re: All students read this sig fig post

Postby Nathan Rothschild_3D » Fri Oct 04, 2019 10:55 am

No you don't have to write out every sig fig. If the final answer is 3 sig figs then you will be fine if you use 3 in the intermediary steps.

SMIYAZAKI_1G
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Re: All students read this sig fig post

Postby SMIYAZAKI_1G » Fri Oct 04, 2019 11:19 am

Jordanmjones13 wrote:Do you know if the problems will specifically tell us how many significant figures to use?


Okay so when it comes to sig figs, it isn't about the problem telling you which places to round up to, but rather it is about how many digits are present in the values provided. For example, had said that problem stated 3.55g, that refers to 3 significant figures. Therefore, you would want to round to that value if what you are doing is multiplication or division. For addition and subtraction, you want to round it to the decimal places. For example, if the problem stated 7.4m, that means you want to round the answer to tenth place for your answer. As the initial post stated, you don't want to try rounding in the middle of the process because that often times messes up by a small margin which can be crucial to the problem.

McKenna_4A
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Re: All students read this sig fig post

Postby McKenna_4A » Fri Oct 04, 2019 1:39 pm

Evamae Bayudan 1B wrote:Will we be penalized for putting extra significant figures?


I think so. But definitely use extra sig figs during calculations

McKenna_4A
Posts: 47
Joined: Sat Aug 24, 2019 12:18 am

Re: All students read this sig fig post

Postby McKenna_4A » Fri Oct 04, 2019 1:39 pm

Evamae Bayudan 1B wrote:Will we be penalized for putting extra significant figures?


I think so. But definitely use extra sig figs during calculations

ahuang
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Re: All students read this sig fig post

Postby ahuang » Sat Oct 05, 2019 10:24 pm

For the upcoming test on Tuesday, will we be penalized for having incorrect sig figs?

405398682
Posts: 20
Joined: Wed Sep 18, 2019 12:21 am

Re: All students read this sig fig post

Postby 405398682 » Sat Oct 05, 2019 11:14 pm

I can easily get confused when I am trying to figure out the sig figs in the calculation of mole/mass using molar mass. Should I just consider the number of sig figs depending on the numbers in the molar mass?

405398682
Posts: 20
Joined: Wed Sep 18, 2019 12:21 am

Re: All students read this sig fig post

Postby 405398682 » Sat Oct 05, 2019 11:15 pm

Should I take sig figs while I am calculating one problem step by step? Should I use sig figs every step or should I just consider the sig figs on the very last calculation?

Abraham De Luna
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Joined: Sat Sep 14, 2019 12:16 am

Re: All students read this sig fig post

Postby Abraham De Luna » Sat Oct 05, 2019 11:21 pm

405398682 wrote:Should I take sig figs while I am calculating one problem step by step? Should I use sig figs every step or should I just consider the sig figs on the very last calculation?

I believe that you should only use significant figures on the last calculation. It is also important to keep in mind that significant figures will be important on the test that we have Tuesday.

Ethan Low 1L
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Joined: Wed Sep 18, 2019 12:15 am

Re: All students read this sig fig post

Postby Ethan Low 1L » Sun Oct 06, 2019 6:45 pm

I think something that helps with the sig fig issue is under appendix 1 in the mastering chemistry textbook, part 1C "Scientific Notation", i think reading that would help illuminate a lot of misconceptions/ preconceived notions behind how to present significant figures.

Adelpha Chan 1B
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Re: All students read this sig fig post

Postby Adelpha Chan 1B » Tue Oct 15, 2019 10:21 pm

405398682 wrote:Should I take sig figs while I am calculating one problem step by step? Should I use sig figs every step or should I just consider the sig figs on the very last calculation?


Keep as many significant figures as you can during the middle steps to ensure you are getting an accurate answer. Rounding for significant figures should only be done in the final step.

Nathan Rothschild_3D
Posts: 40
Joined: Fri Aug 02, 2019 12:15 am

Re: All students read this sig fig post

Postby Nathan Rothschild_3D » Sun Oct 20, 2019 11:50 pm

If you must round sig figs earlier in a problem because something has so many sig figs it is a nuisance to write out then just add 3 sig figs to whatever your final answers number of sig figs should be when rounding. I use this for just cases of multiplication, division, addition, and subtraction. If you are doing something to the power of another I would use an additional 5 sig figs and this generally does not affect my final answer.


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