ph of a salt in a solution

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IWantH2O

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i dont know if this is a stupid question but i havent seen g chem in so long and its killin me (ive been gettin 12's on practice exams)

neways why do FeCl3 and AlCl3 form an acidic solution
i know that

Fe3+ Cl- + h2o----> Fe3+ + HCl + OH- right?

i know that HCl is acidic and OH- is basic so wouldnt the solution be neutral, but i gues im wrong because it says that it will form an acidic solution


please explain

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correct equations:
FeCl3 + 3 H2O --------> Fe(OH)3 + 3 HCl
AlCl3 + 3 H2O-------> Al(OH)3 + 3 HCl

Fe(OH)3 and Al(OH)3 are weak bases while HCl like you said is a strong acid.
strong acid + weak base---> still an acidic solution

memorize the strong bases and acids
strong bases : group 1 hydroxides
strong acids: H2S04, HNO3, HClO4, HBr, HCl, HI
 
i dont know if this is a stupid question but i havent seen g chem in so long and its killin me (ive been gettin 12's on practice exams)

neways why do FeCl3 and AlCl3 form an acidic solution
i know that

Fe3+ Cl- + h2o----> Fe3+ + HCl + OH- right?

i know that HCl is acidic and OH- is basic so wouldnt the solution be neutral, but i gues im wrong because it says that it will form an acidic solution


please explain

use this explanation for test purpose:
1- you learn what are strong acids and strong bases
2- when you see a salt find anion and cation in your salt molecule
3- for your cation(+) add OH-
4-for your anion(-) add H+
5- comapre base and acid you have and which one is stronger
example FeCl3
cation Fe+3 =====> add OH-====> Fe(OH)3
anion Cl- =======> add H+=====>HCl
comapre Fe(OH)3 (base) with HCl(acid)====>
HCl is strong acid and Fe(OH)3 is weak base======> solution is acidic
same for Al(Cl)3
another example:
NaCl
cation Na+=====> add OH- =======> NaOH
anion Cl-======> add H+======> HCl
comapre HCl and NaOH both are strong acid and base======> soultion is netural
another example:
NaH2PO4
Cation Na+====> add OH- =======> NaOH
anion H2PO4- =====> add H+======> H3PO4
compare NaOH and H3PO4 ========> NaOH strong Base and H3PO4 weak acid=====> solution Basic (pH>7)
hope it helped :)
 
use this explanation for test purpose:
1- you learn what are strong acids and strong bases
2- when you see a salt find anion and cation in your salt molecule
3- for your cation(+) add OH-
4-for your anion(-) add H+
5- comapre base and acid you have and which one is stronger
example FeCl3
cation Fe+3 =====> add OH-====> Fe(OH)3
anion Cl- =======> add H+=====>HCl
comapre Fe(OH)3 (base) with HCl(acid)====>
HCl is strong acid and Fe(OH)3 is weak base======> solution is acidic
same for Al(Cl)3
another example:
NaCl
cation Na+=====> add OH- =======> NaOH
anion Cl-======> add H+======> HCl
comapre HCl and NaOH both are strong acid and base======> soultion is netural
another example:
NaH2PO4
Cation Na+====> add OH- =======> NaOH
anion H2PO4- =====> add H+======> H3PO4
compare NaOH and H3PO4 ========> NaOH strong Base and H3PO4 weak acid=====> solution Basic (pH>7)
hope it helped :)

wow ya that makes sense, thanks alot bro.....but how do i know which are strong and which are weak, doi memorize al ofthem? or are the ones listed by albuterol good enough to know
 
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