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Ted Mooney, P.E. RET
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Analysis of Tin Plating Bath Solution
Q. Dear Sirs,
I am trying to find methods of analysis of a Tin Plating bath solution which consists of: Na2SnO3·3H2O = 70 gr/l, NaOH = 11 gr/l, and CH3COONa = 22 gr/l. I have to determine the concentration of Tin Stannate (Na2SnO3·3H2O) (gr/l) and Free Sodium Hydroxide(NaOH)(gr/l) in the above solution. Please, suggest methods.
Thanking in advance,
Chemical Lab - Tanagra, Viotia, Greece
2004
A. Dear friend,
You have to take 5 ml of bath solution add to it 5 ml conc. HCl and 5 ml starch indicator and titrate it against 0.1N Iodine solution. Multiply B.R. by 1.187 you will get the GPL of Stannous.
- Pune, Maharashtra, India
Q. Dear Onkar Kulkarni,
I use the method you suggest for the tin stannic salts but add a nickel catalyst to the tin and HCl and boil to a receiving vessel for 40 mins and titrate as your method. This is time consuming but does work; is your method comparable with mine? I will try your method out.
Many thanks,
- Wrexham
Q. Dear friend
I would like to thank you for your response to the first part of my question, determination of Sodium Stannate. I would really appreciate if you or anybody else could give me a method for the second part of my question that is the determination of Free Sodium Hydroxide in the Tin Plating Solution Bath.
Thank you again,
- Tanagra, Viotia, Greece
A. Dear Fotini
mix 10 ml of vat sample with 50 ml Cl2Ba (10%) and a few drops of thymolphtalein indicator. Titrate with 1N hydrochloric acid to blue end point.
Titre x 4.00 =g/l free NaOH
PS: due to absorption of the indicator by precipitate, add few extra spot of indicator a half way point of titration.
- tehran iran
Dear Hadi, thanks a lot for your response to my question. It will help me very much.
Have a good day.
- Tanagra, Greece
Q. Dear sir,
What is meant by 10 Vat sample in the free alkali test you had mentioned. Please suggest; I am waiting for your response.
- Thane, Maharashtra, Indian
April 14, 2015
A. Hi Manesh. Hadi surely means a 10 ml sample from the vat (tank or bath) of tin plating solution which you wish to analyze. Best of luck with it.
Regards,
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Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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