Titration problem

[chanaka89]

"S" is a 0.05M aq solution of HCl contatining a salt MCl2. [MCl2] in "S" = 0.05M .For a water soluble base M(OH)2 pKb1=6.0 & pKb2=13.0

1)Initial pH
2)Titration curve for the titration of 25.00ml portion of solution S with 0.1M NaOH

Please tell me how to do the calculations to sketch the curve

 

[C.I.D]

bump

 

[C.I.D]

initial pH of what?

 

[Pink panther]

Bump

 

[chanaka89]

initial pH of what?

"S" solution.

 

[C.I.D]

ok...this may be correct..(but check if it's wrong)
initial S solution contains less water soluble salt.therfore u hav to get H+ ions giving from both HCl and MCl2 salt..
first cal pka1 from pkb2 AND cal pka2 from pkb1..
then calculate H+ from MCl2 salt(by neglecting Ka2 coz it's very low) and get the pH..(u knw the equations)..

2.
This is strong acid-strong base titration
but consider the concentration of NaOH is 0.1M AND S solution is=(0.05M) but also consider pH value(from both HCl and MCl2)

 

[C.I.D]

a sample curve