please i need help with those question ,
From our bottle of wine; 3x 100 mL sample replicates were produced and the pH adjusted to pH 7.9 by addition of 4.0 mL of NH4OH (0.5 M) with phosphate buffer. The solution was then coloured with 1.0 mL of 2% (w/v) dye solution and 1.0 mL of 8% (w/v) K3Fe(CN)6 solution. The resulting solutions were left to stand for 15 minutes for colour development. Q4/This reaction is analogous to that shown in the lecture notes, yielding identical products. If phenol compounds are oxidised⦠what reagent is reduced? Write a generalised equation for this reaction. What is the role of the Fe3+ complex? (6 marks) (Graduate Capability - Chemistry knowledge & skills; Graduate Capability â Inquiry/Research) The coloured product can now be separated from solution by performing a trichloromethane (7.5 mL) wash before filtering through solid Na2SO4 to dry the extract. We now assume we have extracted the entire total phenol content of the original samples. Q5/ Is this a safe assumption to make? Which of the preparation steps were we most likely to lose phenol content? How can we quantify the loss, if any, of phenol compounds from our original wine sample? (4 marks) (Graduate Capability - Chemistry knowledge & skills; Graduate Capability â Inquiry/Research)
We now have 6x calibration standards of pure phenol in water (no dye added as yet) and our coloured total phenol sample in trichloromethane. To colour the standards solutions, we have the option of (1) performing dye addition to solution, or (2) performing the dye addition to solution followed by the CHCl3 extraction procedure
which procedure do you follow? If we have originally used distilled, deionized water to dilute our phenol standards, where could a source of contamination arise? (4 marks) (Graduate Capability â Chemistry knowledge & skills; Graduate Capability â Inquiry/Research)
please i need help with those question ,
From our bottle of wine; 3x 100 mL sample replicates were produced and the pH adjusted to pH 7.9 by addition of 4.0 mL of NH4OH (0.5 M) with phosphate buffer. The solution was then coloured with 1.0 mL of 2% (w/v) dye solution and 1.0 mL of 8% (w/v) K3Fe(CN)6 solution. The resulting solutions were left to stand for 15 minutes for colour development. Q4/This reaction is analogous to that shown in the lecture notes, yielding identical products. If phenol compounds are oxidised⦠what reagent is reduced? Write a generalised equation for this reaction. What is the role of the Fe3+ complex? (6 marks) (Graduate Capability - Chemistry knowledge & skills; Graduate Capability â Inquiry/Research) The coloured product can now be separated from solution by performing a trichloromethane (7.5 mL) wash before filtering through solid Na2SO4 to dry the extract. We now assume we have extracted the entire total phenol content of the original samples. Q5/ Is this a safe assumption to make? Which of the preparation steps were we most likely to lose phenol content? How can we quantify the loss, if any, of phenol compounds from our original wine sample? (4 marks) (Graduate Capability - Chemistry knowledge & skills; Graduate Capability â Inquiry/Research)
We now have 6x calibration standards of pure phenol in water (no dye added as yet) and our coloured total phenol sample in trichloromethane. To colour the standards solutions, we have the option of (1) performing dye addition to solution, or (2) performing the dye addition to solution followed by the CHCl3 extraction procedure
which procedure do you follow? If we have originally used distilled, deionized water to dilute our phenol standards, where could a source of contamination arise? (4 marks) (Graduate Capability â Chemistry knowledge & skills; Graduate Capability â Inquiry/Research)
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