Sodium hydroxide used to make standard NaOH(aq) solutions
Chapter 5, Problem 73(choose chapter or problem)
Sodium hydroxide used to make standard NaOH(aq) solutions for acid base titrations is invariably contaminated with some sodium carbonate. (a) Explain why, except in the most precise work, the presence of this sodium carbonate generally does not seriously affect the results obtained, for example, when NaOH(aq) is used to titrate HCl(aq). (b) Conversely, show that if comprises more than 1% to 2% of the solute in NaOH(aq), the titration results are affected.
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