Significant figures clarification

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Christineg1G
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Significant figures clarification

Postby Christineg1G » Sun Sep 29, 2019 2:17 pm

I need some clarification on basic sigfig rules. For example if we end up with the number 0.126358352 after a calculation, how would the correct answer be 1.264 x 10^-2 ?
Last edited by Christineg1G on Sun Sep 29, 2019 2:25 pm, edited 1 time in total.

Ariel Davydov 1C
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Re: Significant figures clarification

Postby Ariel Davydov 1C » Sun Sep 29, 2019 2:19 pm

The number of sig figs in the measurements given in the problem is the same number of sig figs you will use in your final answer. For example, if you are given a mass of 2.35g of a compound, you would use 3 sig figs in your final answer, as what you are given possesses 3 sig figs as well.

Alexa Hernandez 3k
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Re: Significant figures clarification

Postby Alexa Hernandez 3k » Sun Sep 29, 2019 2:25 pm

It depends on how you obtained that number. If you used division or multiplication, then the number of significant figures will be determined by the original number with the least amount of significant figures. For Example: 2.5 x 3.42 , 2.5 has the smallest amount of sig. figures with only 2 (you will round of once you get 2 significant figures). Answer: 8.6.

EmilyJoo_1G
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Re: Significant figures clarification

Postby EmilyJoo_1G » Mon Sep 30, 2019 9:58 pm

There's a helpful document on Dr Lavelle's Chem 14A website on determining significant figures. The number in the problem with the least amount of sigfigs determines the number of sigfigs in your answer because the final value shouldn't be more precise/accurate than the least precise value.


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