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October 21, 2025, 06:51:30 pm
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Author Topic: Is my answer right to this question or is the exam's answer right?  (Read 499 times)  Share 

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Starlight

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Is my answer right to this question or is the exam's answer right?
« on: May 22, 2012, 09:48:36 pm »
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'3-Methylbutanol' has formula C5H120. What is the mass of oxygen in 1.204 x 10^10 molecules of 3-methylbutanol?

The answer i get is 1.78 x 10^-3 g

but the answer the sample exam gives is 3.20 x 10^-4 g?

Am I wrong??
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amilss

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Re: Is my answer right to this question or is the exam's answer right?
« Reply #1 on: May 22, 2012, 10:01:39 pm »
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n(3-methyl butanol) = N/NA
                                = 1.204x10^10/6.02x10^23
                                = 2x10^-14

m(O) = 2x10^-14 x 16
         = 3.2x10^-13 grams



Im getting the wrong power but that seems right to me?
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