SI UNITS

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Matlynn Giles 2E
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SI UNITS

Postby Matlynn Giles 2E » Tue Oct 13, 2020 9:12 am

Specifically for Dr. Lavelle's class, how many sig figs should we be using? To the right of the deciemal point, how high should we go up?

Jasmin Kumar 1G
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Re: SI UNITS

Postby Jasmin Kumar 1G » Tue Oct 13, 2020 9:33 am

There is a page on his website that has all of the rules of sig figs. For problems, you would match sig figs of the number that has the lowest sig figs, which should determine how many numbers to the right of the decimal point you should put in your answer.

Sid Panda 3A
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Re: SI UNITS

Postby Sid Panda 3A » Tue Oct 13, 2020 9:37 am

705418914 wrote:Specifically for Dr. Lavelle's class, how many sig figs should we be using? To the right of the deciemal point, how high should we go up?


Agree with the person above me. Here is the link (https://lavelle.chem.ucla.edu/wp-conten ... OUT_SF.pdf) to that document Dr. Lavelle posted about sig figs.

OwenSumter_2F
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Re: SI UNITS

Postby OwenSumter_2F » Tue Oct 13, 2020 10:09 am

Also, try not to round your numbers until the final answer, or else your answer may be off a couple of decimal points.

Kiran Singh 3A
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Re: SI UNITS

Postby Kiran Singh 3A » Tue Oct 13, 2020 10:11 am

The number of sig figs to use usually depends on how many sig figs the values in the problem you are solving have. For example, if a problem said that the sample of NaCl was 1.05 g (which has 3 sig figs) and contained other additional values that had 3 sig figs or more, your answer would need to contain 3 sig figs. While working on the problem, it would probably be best to use non-rounded values since you would be using a calculator.

Nadya Higgins 3F
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Re: SI UNITS

Postby Nadya Higgins 3F » Tue Oct 13, 2020 10:21 am

Yeah as everyone has been saying, you can't choose to put a certain amount of sig figs for for every problem. Calculations are as precise as the least precise measurement/number. So, generally, depending on the problem, you could have 3 sig figs or 4 sig figs in your final answer if the number with the lowest amount of sig figs in your calculations have 3 sig figs or 4 sig figs respectively.

Ravdeep Warar 2G
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Re: SI UNITS

Postby Ravdeep Warar 2G » Tue Oct 13, 2020 2:53 pm

Adding onto what everyone above said, the problems so far have not said anything with specific instructions for how many sig figs the answer should have, so it is best to pay attention to the numbers given in the problem.

Eunice_Castro_1G
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Re: SI UNITS

Postby Eunice_Castro_1G » Wed Oct 14, 2020 11:17 pm

There are rules to determine how many significant figures you should be using. It will always depend on the problem. There are rules available on his website. Hope this helps!

Alexandra Salata 2L
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Re: SI UNITS

Postby Alexandra Salata 2L » Thu Oct 15, 2020 6:33 am

It really depends on the problem and if they specify It or not. When they do not specify, I just like to go with 3 sig figs because its the most standard way of rounding up figures and in the past I have been taught to do this by teachers

Talia Dini - 3I
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Re: SI UNITS

Postby Talia Dini - 3I » Fri Oct 16, 2020 12:23 am

Hi! I believe that the number of sig figs in your answer depends on the lowest number of sig figs in the problem that was given to you.

Julianna Shimabukuro 1D
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Re: SI UNITS

Postby Julianna Shimabukuro 1D » Fri Oct 16, 2020 12:49 am

The amount of sig figs depends on the lowest number of sig figs in the numbers within the problem, or if you're adding the masses of elements from the periodic table, you use the lowest amount of sig figs for your answer when adding the masses together. However, I would not advise you to use sig figs until your final answer to avoid having an answer that might be slightly off due to rounding for sig figs.

Juliana Rosales 1H
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Re: SI UNITS

Postby Juliana Rosales 1H » Sun Oct 18, 2020 9:06 pm

I would go with how ever many figures are in any values mentioned in the question, just to be consistent.

Brandon Carris
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Re: SI UNITS

Postby Brandon Carris » Sun Oct 18, 2020 11:41 pm

yea usually the values in the question should determine the number of sig figs you put in your answer.


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