Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: L3ng on June 30, 2013, 11:22:37 AM
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The above-mentioned standard solution was used to titrate a 25.171-g sample of a KSCN solution. An end point was obtained after adding 23.765 g of the AgNO3 solution. Calculate the molality of KSCN solution.
The above standard solutions were used to determine the BaCl2.2H2O in a 0.7120-g sample.
A 20.102-g sample of the standard AgNO3 was added to a solution of the sample, and the excess AgNO3 was back-titrated with 7.543 g od the KSCN solution. Calculate the percent BaCl2.2H2O in the sample. :-*
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You have to show your attempts at solving the question to receive help. This is a forum policy.
No solution was mentioned above, so there is no way to help you.
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help us to help you by at least telling us, what the "above mentioned standard solution(s)" might be
then go on to help yourself, by at least trying to figure out what the general idea with solving those problems might be, and writing about it, along the way trying to apply a bit 'bout this idea to these tasks , so we can figure out where the core of your problem might be:
no use in doing your homework for you , but a lot of sense in improving your knowledge, so you'll be able to do it all by yourself afterwards
regards
Ingo
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The above-mentioned standard solution was used to titrate a 25.171-g sample of a KSCN solution. An end point was obtained after adding 23.765 g of the AgNO3 solution. Calculate the molality of KSCN solution.
The above standard solutions were used to determine the BaCl2.2H2O in a 0.7120-g sample.
A 20.102-g sample of the standard AgNO3 was added to a solution of the sample, and the excess AgNO3 was back-titrated with 7.543 g od the KSCN solution. Calculate the percent BaCl2.2H2O in the sample. :-*
A 0.1752-g sample of primary standard AgNO3 was dissolved in 502.3 g of distilled water.
Calculate the molality of Ag+ in this solution.
this is the 1st part of the ques that i missed it...
juz tell me the idea about the method to solve..thx
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Start with reaction equations.
Would you be able to solve the problem given volumes, not masses?
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help us to help you by at least telling us, what the "above mentioned standard solution(s)" might be
then go on to help yourself, by at least trying to figure out what the general idea with solving those problems might be, and writing about it, along the way trying to apply a bit 'bout this idea to these tasks , so we can figure out where the core of your problem might be:
no use in doing your homework for you , but a lot of sense in improving your knowledge, so you'll be able to do it all by yourself afterwards
regards
Ingo
A 0.1752-g sample of primary standard AgNO3 was dissolved in 502.3 g of distilled water.
Calculate the molality of Ag+ in this solution.
this is the 1st part of the ques that i missed it...
can give me some clues?? i dunoe hw to solve the last part...
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Start with reaction equations.
Would you be able to solve the problem given volumes, not masses?
i am not sure about the problem for last part..
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help for starters:
start by looking up "silver" and "thiocyanate", and try to figure out , what might happen if you mix a waterbased solution of silver nitrate with a waterbased solution of potassium thiocyanate
this is the first riddle to solve
after you figured that one out, write an equation belonging to which expresses both the qualitative process as as the quantitative situation
then think about why recalculating everything to mole might be helpful in this case
should any questions arise, pls. come back and describe what you found out (and where you're lost), so we can keep informing you with useful hints
regards
Ingo
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help for starters:
start by looking up "silver" and "thiocyanate", and try to figure out , what might happen if you mix a waterbased solution of silver nitrate with a waterbased solution of potassium thiocyanate
this is the first riddle to solve
after you figured that one out, write an equation belonging to which expresses both the qualitative process as as the quantitative situation
then think about why recalculating everything to mole might be helpful in this case
should any questions arise, pls. come back and describe what you found out (and where you're lost), so we can keep informing you with useful hints
regards
Ingo
BaCl2∙2H2 O+2AgNO3→Ba(NO3 )2+2AgCl+2H2O
is this a equation required?
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we're looking for some equation of this structure, yes
... except we're not dealing with barium chloride (BaCl2 , or BaCl2 x 2 H2O as dihydrate) , but with potassium thiocyanate instead
(hence, the insoluble salt formed won't be silverchloride , but another insoluble silver salt instead )
look up "potassium thiocyanate" and try to modify your equation accordingly
regards
Ingo
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BaCl2∙2H2 O+2AgNO3→Ba(NO3 )2+2AgCl+2H2O
is this a equation required?
Yes - this is ONE of the reaction equations required. But you need another one first.