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

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


1 Answers

Askiitians Expert Sahil Arora - IITD
19 Points
12 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:-

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