December 22, 2024, 07:33:16 AM
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Topic: Use the average atomic mass of Oxygen to calculate the average atomic mass of X.  (Read 7961 times)

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Offline stryker23

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I can't figure this probelm out, and it should be simple. 

"A certain element X forms a compound with oxygen in which there are two atoms of X for every three atoms of oxygen. In this compound, 4.63 g of X are combined with 1.59 of oxygen."
   
1. Use the average atomic mass of oxygen to calculate the average atomic mass of X.
2. Use your calculated atomic mass to identify the element X. Enter the chemical symbol of the element.

I attempted to find how many moles of oxygen were in the sample by taking 1.59g/15.9994.  I then assume I need to some how apply the 2/3 ratio and then multiple by the sample of X (4.63).  Every way I have tried this I just come out with a very small number.  What is the correct way to work this out?

Offline Borek

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and then multiple by the sample of X (4.63)

Think it over. Close, but no banana ;)
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Offline stryker23

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I don't understand, so I don't multiple the amount of moles of X by the sample size of X?  I thought my problem was in how I applied the ratio.

Offline Sev

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Multiply the number of moles of O by 2/3 to get moles of X.  Divide the mass of X (4.63g) by the number of moles to obtain the molecular mass.

Offline stryker23

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Thank you very much.  I have been trying to figure that out for forever.  I knew I was just doing something stupid.  It was so simple.

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