Chemical and Ionic Equilibrium - Result Question 134

####76. The dissociation constant of a weak acid HA is 4.9×108. After making the necessary approximations, calculate (i) pH

(ii) OHconcentration in a decimolar solution of the acid. (Water has a pH of 7).

(1983,2M)

Show Answer

Solution:

  1. Ksp (AgI)=8.5×1017=[Ag+][I]

[I]required to start precipitation of AgI

=8.5×10170.10=8.5×1016M Ksp (HgI2)=2.5×1026=[Hg2+][I]2

[I]required to start precipitation of HgI2

=2.5×10260.10=5×1013M

The above calculation indicates that lower [I]is required for precipitation of AgI. When [I]reaches to 5×1013, AgI gets precipitated almost completely.

When HgI2 starts precipitating,

[Ag+]=8.5×10175×1013=1.70×104M 



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक