Analytical Chem Uncertainty Problem- Time Sensitive!

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IAmNotaMeatball
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Analytical Chem Uncertainty Problem- Time Sensitive!

Post by IAmNotaMeatball »

I've been struggling with this question for a while.

Calculate the molar mass of diethyl ether, CH3CH2OCH2CH3. (C = 12.0106 +/- 0.0010, H = 1.00798 +/- 0.00014, O = 15.9990 +/- 0.0008)

The molar mass isn't an issue for me, but the uncertainty is giving me trouble. I've tried absolute error, as it's additive (taking into consideration the ratios of the molecules) but that didn't work.

The error is apparently +/- 0.004 g/mol, but I still have no idea how to get there.

Please help. My midterm is tomorrow.
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ChenBeier
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Post by ChenBeier »

The highest value is important.

You have 4 Carbons, what means +-0,001 times 4 is +-0,004 g/mol

Hydrogen is 10 times +- 0,00014 = 0,0014 g/mol

and oxygen one time +-0,0008 g/mol

So the error is +-0,004 g/mol max/min
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