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#1 2014-02-15 04:16:37
How many moles?
12 g of X[sub]2[/sub]O[sub]5[/sub], an oxide of element X contains 7.2g of X. How many moles of X does 7.2g of the element contain?
Also, explain me how to do this.
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#2 2014-02-15 08:12:16
- Bob
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Re: How many moles?
hi Agnishom,
This is what my better half says:
12g of compound and 7.2g of X means there are 4.8g of oxygen.
1 mole of oxygen weighs 16g
So there are 4.8/16 moles of oxygen = 0.3
X : O = 2 : 5 => moles of X = 2/5 of 0.3 = 0.12
That finishes the question but here's some more:
0.12 moles is 7.2g => 1 mole is 7.2/0.12 = 60
So X has a relative atomic mass of 60.
Checked out the periodic table .... nope ...... so X is just made up for the purposes of the question.
Bob
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#3 2014-02-15 10:29:52
- ShivamS
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- Registered: 2011-02-07
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Re: How many moles?
There are 0.12 moles of X in 7.2g of X.
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#4 2014-02-15 13:13:59
Re: How many moles?
OK, thank you all
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#5 2014-02-17 05:17:58
- ShivamS
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Re: How many moles?
By the way, you can find full solutions to NCERT questions (presuming this is one) on meritnation for free.
Last edited by ShivamS (2014-02-17 05:18:11)
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