• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Preparing benzoic acid from benzylalcohol

Extracts from this document...


Maximilian Ziegler 3IB Preparing benzoic acid from benzylalcohol Planning (a) Problem The aim of this experiment is to synthesize benzioc acid, with the highest possible yield, by oxidizing benzylalcohol. Hypothesis We expect the percentage yield to be about 50% due to several processes such as cooling and filtering. Possible Variables - Time - Temperature (of water) - Filter Planning (b) Apparatus/ Materials - Round bottomed flask under reflux - benzylalcohol - HCl - Na2O4 - B�chner funnel - beakers - sodium carbonate Procedure The benzioc acid is synthesized by heating benzylalcohol in a round bottomed flask under reflux. In addition to that, we use Na2O4 as a oxidizing agent. After that, we use HCl to precipitate it. After the some time, we filter it through a B�chner funnel before it is recrystallized and filtered again. ...read more.


Hence, the theoretical yield is 100% by amount of mol. Molar mass Benzylalcohol 108 g/mol Benzoic acid 122 g/mol Initial amount of benzylalcohol: Amount of benzoic acid at completion: Percentage yield: Conclusion The actual yield was about 27%. That means the underestimated processes of purification such as stated in the hypothesis. The amount of the produced benzoic acid in this experiment was probably higher than the amount we have obtained in the end, because the number of impurities in the final product were eminently lower than the amount of lost benzoic acid due to purification processes. After all, it is quite certain that the final product was benzoic acid based on the fact that, according to tests, it was aromatic and acidic. ...read more.


An obvious amount was left in the filter after the dissolved benzoic acid was precipitated due to the cooling of the solution on the funnel. It is reasonable to assume that the obtained benzoic acid was quite pure, so that impurities were just a small part of the mass of the final product. Suggestions of improvement: - increase the number of purification processes to reduce the amount of impurities, even though, that might result in a lower percentage yield do to the fact that some of the benzoic acid might be lost in processes, such as filtering - when the acid runs through the filter, to filter out impurities, the filter and the funnel should be warm and the solution heated more to make sure that neither the acid precipitates nor is filtered out --> higher percentage yield - prevent unintentional cooling and precipitation of the acid by being faster with filtering out impurities --> higher percentage yield ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Aqueous Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Aqueous Chemistry essays

  1. How much Iron (II) in 100 grams of Spinach Oleracea?

    G. Bulon, J. Holman, J. Lazonby, G. Pilluis, D.Waddington Heinemann The Bath Press-Bath (2000) 5) El 2.1 How much Iron is in a sample of an Iron compound? Salters Advanced Chemistry (2000) 6) Understanding Chemistry for Advanced Level (Third Edition) Ted Lister and Janst Renshaw Stanley Thornes Publishers-Cheltenham (2000)

  2. Recrystallization - choose the most appropriate solvent to obtain a successful recrystallization of benzoic ...

    The filter paper with the crystals is transferred onto a fresh piece of filter paper and allows the crystals to air-dry. 12. Once the crystals are dry, all the standard things is did with them: Determine % recovery, take a melting point.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work