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acid base titration

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13. A hydrocholoric acid solution is standardinzed by titrating 0.4541 g of primary stardard tris(hydroxymethyl)aminomethane. If 35.37 mL is required for the titration, what is the molarity of the acid?

15. A sodium hydroxide solution is standardized by titrating 0.8592 g of primary standard potassium acid phthalate to a phenolphthalein end point, requiring 32.67 mL. What is the molarity of the base solution?

18. Calculate the pH at 0, 10.0, 25.0, and 30.0 mL of titrant in the titration of 50.0 mL of 0.100 M NaoH with 0.200 M HCl.


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13. The molar weight of TRIS is 121.14 g/mol. So the moles of 0.4541 g of TRIS is

At the end of the titration, the moles of the two chemicals are equal to each other.
So the molarity of HCl is

The molarity of HCl is 0.10526 M.

15. The molar weight of KHP is 204.2g/mole.
So the moles of 0.8592 g of KHP is

At the end ...

Solution Summary

If provides examples of finding the molarity and pH of the solution during the titration process.