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Physical Chemistry

If the dissociation constant of HCN is 4.8 X 10-10 mol dm-3, then the pH of 0.25 mol dm-3 NaCN solution is

Profile image of Nehal Wani
16 Years agoGrade
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1 Answer

Profile image of Askiitians Expert Sahil Arora - IITD
16 Years ago

Dear Nehal

As NaCN is a salt of strong base and weak acid

So pH =  1/2pKw +  1/2pKa +  1/2log C

= 7 + 1/2pKa +  1/2log C.

 

 

 

 

Put Ka=4.8 X 10-10 mol dm-3 and C=0.25 mol/dm3.

we get pH=8.55

for more details read:-

http://www.askiitians.com/iit-jee-chemistry/physical-chemistry/salt-of-weak-acid-and-strong-base.aspx

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All the best Nehal !!!




Regards,

Askiitians Experts

Sahil Arora

 

 

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