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

Equilibrium Constant for esterification

Extracts from this document...

Introduction

Chemistry Experiment 15 (a) Title: Equilibrium Constant for esterification (b) Aim: To find out the equilibrium constant for esterification of ethanoic acid and propan-1-ol. (c) Theory: In the presence of conc. H2SO4 and under reflux, ethanoic acid undergoes a reversible reaction with propan-1-ol to form ester and water. As equilibrium is reached, CH3COOH(l)+CH3CH2CH2OH(l) CH3COOCH2CH2CH3(l)+H2O(l) Kc = By titrating the reaction mixture with standard alkali solution before and after refluxing, the quantity of the acid used, and thus the quantities of the alcohol used as well as of the ester and water formed can be determined. Knowing the quantities or molar concentrations of the species present in the equilibrium mixture, the equilibrium constant, Kc can be calculated. Set-up: (d) Result: Titration of 8 drops of H2SO4 against NaOH Titration 1 (trial) 2 Final burette reading (cm3) 15.1 30.2 Initial burette reading (cm3) 0 15.1 Volume of NaOH used (cm3) ...read more.

Middle

of moles of CH3COOH reacted in 1 cm3 of mixture = 8.75 x 10-3 mol - 3.65 x 10-3 = 5.10 x 10-3 mol No. of moles of CH3CH2CH2OH in 1 cm3 of reaction mixture after heating = No. of moles of H+ from 1 cm3 of CH3COOH = 3.65 x 10-3 mol No. of moles of CH3COOCH2CH2CH3 in 1 cm3 of reaction mixture after heating = No. of moles of H+ reacted in 1 cm3 of CH3COOH = 5.10 x 10-3 mol No. of moles of H2O in 1 cm3 of reaction mixture after heating = No. of moles of CH3COOCH2CH2CH3 = 5.10 x 10-3 mol Therefore, Kc = (5.10 x 10-3 x 5.10 x 10-3) (3.65 x 10-3 x 3.65 x 10-3) = 1.95 When comparing with the theoretical value (Kc=3.00), Percentage error = [(1.95 - 3.00) / 3.00] x 100% = - 35% (e) ...read more.

Conclusion

3. If the NaOH needed for the end-point of titration is constant, it indicates that the concentration of the reacting substances do not have further changes, meaning that the esterification process has completed and reached an equilibrium. 4. (i) The number of moles of NaOH required for complete neutralization with H2SO4 and also the CH3COOH in the reaction mixture will not be accurate, causing errors when estimating the number of moles of the 8 drops of the added H2SO4 and also that of the CH3COOH reacted. Hence, the equilibrium constant obtained will be inaccurate. (ii) Since the actual volume of the reaction mixture was lower than the expected one, the concentration of the former would be higher than the latter. Since the volume after mixing the reactants is used to determine the concentration of the 4 reactants, the equilibrium constant obtained will be inaccurate. (g) Conclusion: The equilibrium constant (Kc) for the reaction CH3COOH(l)+CH3CH2CH2OH(l) CH3COOCH2CH2CH3(l)+H2O(l) is 1.95, with an percentage error of -35% ?? ?? ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Organic 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 AS and A Level Organic Chemistry essays

  1. The aim of this experiment is to produce Aspirin. This is an estrification in ...

    The solution was then washed of the glass rod to ensure none is lost. The 500cm3 standard flask was washed three times and using a filter funnel the solution was carefully transferred in to it. The beaker and funnel was then rinsed several times making sure that all the solution has gone into the standard flask.

  2. Esterfication. he purpose of this lab is to achieve a specific odour through ...

    catalyst in order to speed up the process but it does not undergo a chemical change itself. 2. The odour will be enhanced through the process of pouring it on ice because of the fact that esters are not soluble in water.

  1. investigating the amount of ascorbic acid present in fruit

    Spatula Used at the start of the investigation when transferring the solid KI and acetic acid. Burette (50cm3) Will be used to pour in the NBS solution and to read off my titre when I have reached end point. Measuring Cylinder (100cm3 )

  2. Aim: To determine how the concentration of each species in a reaction affects the ...

    the order of reaction with respect to the concentration of each species is known, both the value and units of k can be calculated. The rate equation can be used in order to check whether calculations have been correct. When k has been calculated, and the order of reaction with

  1. Finding the concentration of an acid sample

    Rinse funnel with distilled water 7. Now add distilled water until the bottom of the meniscus is level with the line when looked at, at eye level 8. Set up the burette filling it with the acid solution and placing it in the stand.

  2. Comprehensive and Detailed Chemistry notes

    The intensity of the selected beam is measured 6. Photomultiplier tubes then convert this this measurement into eectrical signals -- The grater the concentration, the greater the amount of light absorbed -- AAS is a very sensitive process whereby concentrations of elemnts in ppm can be detected and sometimes in ppb.

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