The Total solution for NCERT class 6-12
The first ionization constant of H2S is 9.1 × 10–8. Calculate theconcentration of HS– ion in its 0.1 M solution. How willthis concentration be affected if the solution is 0.1 M in HCl also? If thesecond dissociation constant of H2S is 1.2 × 10–13, calculate theconcentration of S2– under both conditions.
(i) To calculate theconcentration of HS– ion:
Case I (in theabsence of HCl):
Let the concentration of HS– be x M.
Case II (in thepresence of HCl):
Inthe presence of 0.1 M of HCl, let be y M.
(ii) Tocalculate the concentration of:
Case I (in theabsence of 0.1 M HCl):
(Fromfirst ionization, case I)
Case II (in thepresence of 0.1 M HCl):
Again, let the concentration of HS– be X’ M.
(Fromfirst ionization, case II)
(FromHCl, case II)