Molar Mass Sig Figs

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AustinMcBrideDis3L
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Molar Mass Sig Figs

Postby AustinMcBrideDis3L » Mon Oct 05, 2020 5:31 pm

Does anyone know how many sig figs we should take from the molar masses on the periodic table for our homework and problems? Also which is preferred: rounding or truncating?

Ryan_Kien_1L
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Re: Molar Mass Sig Figs

Postby Ryan_Kien_1L » Mon Oct 05, 2020 5:34 pm

I think the general rule of thumb is to go with 4 sig figs off the periodic table and to go with rounding.

Stacey Phan 2I
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Re: Molar Mass Sig Figs

Postby Stacey Phan 2I » Mon Oct 05, 2020 5:57 pm

When you write the molar masses from the periodic table, people typically use four sig figs (to the hundredths place).

Peter DePaul 1E
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Re: Molar Mass Sig Figs

Postby Peter DePaul 1E » Mon Oct 05, 2020 6:01 pm

My chemistry and AP Chem teachers taught us to use 4 sig figs

Nina Tartibi 1F
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Re: Molar Mass Sig Figs

Postby Nina Tartibi 1F » Mon Oct 05, 2020 6:25 pm

I believe it is 4 decimal places when dealing with chemical substances and problems.

Yuehan_Wu_3K
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Re: Molar Mass Sig Figs

Postby Yuehan_Wu_3K » Thu Oct 08, 2020 5:06 am

4 decimal will be fine for the most situations.

David Jen 1J
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Re: Molar Mass Sig Figs

Postby David Jen 1J » Thu Oct 08, 2020 10:14 pm

I also use 4 sig figs.

Linette Choi 3L
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Joined: Wed Sep 30, 2020 9:51 pm

Re: Molar Mass Sig Figs

Postby Linette Choi 3L » Fri Oct 09, 2020 7:16 pm

Typically I use exactly the molar mass that is given from my periodic table (which rounds the decimals to the hundredth place). However, using 4 decimal places is a safer method to get a more accurate answer.

joshtully
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Joined: Wed Sep 30, 2020 9:36 pm

Re: Molar Mass Sig Figs

Postby joshtully » Sun Oct 11, 2020 5:01 pm

I do 2 sig figs after the decimal point, which usually means 4 sig figs total.

805421690
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Re: Molar Mass Sig Figs

Postby 805421690 » Sun Oct 11, 2020 11:52 pm

I usually keep it to three, unless the fourth one is higher than five. If it is I just keep it to if I am calculating that number, but if its for the final answer I just round it up or drop it. Hope that helps


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