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Topic: Atomic mass of an unknown element  (Read 7939 times)

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Offline dipndots

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Atomic mass of an unknown element
« on: September 20, 2007, 11:32:39 PM »
So heres the question:

It is found that 0.119g of element Z contains 1.50 x 10^21 atoms. The atomic mass of Z is..

Offline Yggdrasil

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Re: Atomic mass of an unknown element
« Reply #1 on: September 21, 2007, 12:40:38 AM »
Please read the Forum Rules.  You should that you've at least attempted to answer the problem before we will help you.

Offline Padfoot

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Re: Atomic mass of an unknown element
« Reply #2 on: September 21, 2007, 04:26:21 AM »
What is atomic mass?

Offline dieded

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Re: Atomic mass of an unknown element
« Reply #3 on: September 22, 2007, 06:30:21 AM »
Remember the Avogadro constant .

Approximately 6 * 10^23 atoms of Z will make up the atomic mass of Z.

And Yggdrasil you should at least at least help out dipndots a bit.

Offline Borek

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Re: Atomic mass of an unknown element
« Reply #4 on: September 22, 2007, 07:24:30 AM »
Mass of 5 marbles is found to be 3 g, what is a mass of a dozen?
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline kiet

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Re: Atomic mass of an unknown element
« Reply #5 on: September 22, 2007, 09:33:12 AM »
  1 mol atoms has 6.023 x 10^23 atoms
We know that  n =(the amount of atoms)/(6.023x10^23)
               => n = (1.50x10^21)/(6.023X10^23) =0.00249 (mol)
   and m=nxM => M=m/n=0.119/0.00249=47.79
So the atomic mass of the element Z is approximately 47.8
Z is Titanium.

Offline dipndots

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Re: Atomic mass of an unknown element
« Reply #6 on: September 27, 2007, 09:44:04 PM »
I got it. omg thanks. Seems simple when u explained it

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