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#1 sarmad

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Posted 02 April 2006 - 03:52 PM

i'm stuck on this question and i dont know how to resolve it?

a mixture of sodium chloride and sodium sulphate is known to contain 0.5 mol sodium ions and 0.2 mol of chloride ions.

how many moles of Sulphate ions are present?


#2 ad absurdum

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Posted 02 April 2006 - 04:18 PM

QUOTE(sarmad @ Apr 2 2006, 04:52 PM) View Post

i'm stuck on this question and i dont know how to resolve it?

a mixture of sodium chloride and sodium sulphate is known to contain 0.5 mol sodium ions and 0.2 mol of chloride ions.

how many moles of Sulphate ions are present?


NaCl and (Na2)SO4

There is 0.2 mol of chloride ion, in the NaCl there must be the same number of moles of each ion, so there must be 0.2 mol of sodium. This leaves 0.3 mol of sodium in the other ionic compound. In this, there are two sodium ions for every one sulphate ion, so if there is 0.3 mol of sodium there must be 0.15 mole of chloride. I think.
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#3 sarmad

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Posted 02 April 2006 - 06:59 PM

QUOTE(ad absurdum @ Apr 2 2006, 05:18 PM) View Post

QUOTE(sarmad @ Apr 2 2006, 04:52 PM) View Post

i'm stuck on this question and i dont know how to resolve it?

a mixture of sodium chloride and sodium sulphate is known to contain 0.5 mol sodium ions and 0.2 mol of chloride ions.

how many moles of Sulphate ions are present?


NaCl and (Na2)SO4

There is 0.2 mol of chloride ion, in the NaCl there must be the same number of moles of each ion, so there must be 0.2 mol of sodium. This leaves 0.3 mol of sodium in the other ionic compound. In this, there are two sodium ions for every one sulphate ion, so if there is 0.3 mol of sodium there must be 0.15 mole of chloride. I think.


thanks, that was really helpful!

#4 YIC

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Posted 22 April 2006 - 03:36 PM

this question always comes up in MC's

I can't even remember how to do them, although I remember that when I learned it, it was very easy





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