9. A student carries out a titration to determine the molar mass of an unknown acid, A • The student dissolves 2.24 g of acid A in distilled water and makes the solution up to 250.0 cm. The student titrates a 25.0 cm" portion of this solution with 0.120 mol dm NaOH. 25.25 cm of 0.120 mol dm NaOH are required to reach the end point. (a) Name the apparatus that the student should use to • make up the acid solution to 250.0 cm measure the 25.0 cm' portion of acid solution. make up the acid solution to 250 cm: ....... measure the 25.0 cm' portion: (b) The acid reacts with NAOH in a 1:1 molar ratio. Calculate the molar mass of acid A. molar mass of acid A = g mol (c) The student is not confident that their titre is accurate. Suggest what the student should do next to reduce the effect of any random error in the titration. ....**... .....*..

9. A student carries out a titration to determine the molar mass of an unknown acid, A • The student dissolves 2.24 g of acid A in distilled water and makes the solution up to 250.0 cm. The student titrates a 25.0 cm" portion of this solution with 0.120 mol dm NaOH. 25.25 cm of 0.120 mol dm NaOH are required to reach the end point. (a) Name the apparatus that the student should use to • make up the acid solution to 250.0 cm measure the 25.0 cm' portion of acid solution. make up the acid solution to 250 cm: ....... measure the 25.0 cm' portion: (b) The acid reacts with NAOH in a 1:1 molar ratio. Calculate the molar mass of acid A. molar mass of acid A = g mol (c) The student is not confident that their titre is accurate. Suggest what the student should do next to reduce the effect of any random error in the titration. ....**... .....*..

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter15: Acid–base Equilibria

Section: Chapter Questions

Problem 98AP

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