3 only 3. A 0.3246 g sample that might contain NaOH, Na₂CO,, NaHCO, or a permissiblemixture of the bases is titrated with 0.0828 M HCl by the double-indicatormethod. It is found that 30.38 ml of the acid are required to reach thephenolphthalein end point. Methyl orange is then added to the solution and thetitration continued using an additional of 7.83 ml of the acid. Calculate the % ofeach in the sample?4. The protein in a 1.2846-g sample of an oat cereal is determined by the Kjeldahlprocedure for organic nitrogen. The sample is digested with H₂SO4, the resultingsolution made basic with NaOH, and the NH, distilled into 50.00 mL of 0.09552 MHCI. The excess HCI is then back titrated using 37.84 mL of 0.05992 M NaOH.Given that the protein in grains averages 17.54% w/w N, report the % w/wprotein in the sample of cereal.

To calculate the percentage of each compound (NaOH, Na2CO3, NaHCO3, Na2C2O4, or a mixture) in the…

3. A 0.3246 g sample that might contain NaOH, Na₂CO,, NaHCO, or a permissible mixture of the bases is titrated with 0.0828 M HC by the double-indicator method. It is found that 30.38 ml of the acid are required to reach the phenolphthalein end point. Methyl orange is then added to the solution and the titration continued using an additional of 7.83 ml of the acid. Calculate the % of each in the sample?

3. A 0.3246 g sample that might contain NaOH, Na₂CO,, NaHCO, or a permissible mixture of the bases is titrated with 0.0828 M HC by the double-indicator method. It is found that 30.38 ml of the acid are required to reach the phenolphthalein end point. Methyl orange is then added to the solution and the titration continued using an additional of 7.83 ml of the acid. Calculate the % of each in the sample?

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter7: Neutralization Titrations And Graphical Representations

Section: Chapter Questions

Problem 1P

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