The Equilibrium Constant of an Ester Hydrolysis Reaction Abstract The first step in determining the equilibrium constant of an ester hydrolysis reaction is to prepare five different reaction mixtures with the volume given in Table 1. the bottles have different mixtures of HCl, H2O, an unknown ester, and one bottle has alcohol. We will later determine the equilibrium constant for the reaction between the unknown ester and water to produce an unknown alcohol, and unknown acid. Once the bottles were shooken vigorusly we stored them in our drawer until chemical equilibrium was reached, which took about two weeks. We were then to make a base solution of 0.7 M NaOH. In order to standardize this solution we had to weigh out 5g of KHP, which is the amount needed to neutralize 35ml of our base. Once we weighed out the KHP we then dissolved it in 50 ml of water, and finally titrated the base three different times, we could then take the average and find the molarity of the NaOH solution. After the bottles hadbeen sitting for 2 weeks we titrated each one with the base and recorded how much base was needed in (ml). Once we titrated all the bottles we then had all theinformation we needed in order to finish the calculations. Intro In this lab we are trying to determine and equilibrium constant of an ester hydrolysis reaction. What happens in this reaction is water and an unknown ester are forming an unknown alcohol an organic acid, which is catalyzed with HCL. The process in which both the water and ester split and recombine to produce the alcohol and acid is called hydrolysis. These products are all based on functional groups, or patterns in the... ... middle of paper ... ...t the ester and H20 produce the alcohol and acid so the results in bottle 1 are no suprise, No reactant no product. In bottle 2 we have the most initial ester, and we produce the most acid and alcohol. In bottle 3 we still have a good amount of ester but with water added in, which gives us a good amount of product, and a little bit more water at the end. In bottle 4 we put a little ester in with more water than last time, less products were formed, and most of the ester was used so there isnt much left at the end. Finally, bottle 5 was different than the rest. We started with a little bit of alcohol we ended up with mixed results. There was alcohol left over and a little acid was made, while alot of water was made. Basically all we need is water and an ester and we will end up with an organic acid produced as well as an alcohol.
Then titrate with the sodium thiosulfate solution as in the standardization procedure, adding 6 drops of starch indicator near the end of the titration. Record the volume of thiosulfate solution used in the titration. Make a duplicate
this is the best volume to use as it is about ¾ of a test tube full,
10cm3 of 1 molar solution. I will use 3 of each solution to ensure that
1 ml 0.1M succinate. .2 ml enzyme tube 3. -5.8 ml pH 9 buffer 1 ml 0.1M succinate.
and set the up to one of the stands and then measure out 30ml of
b. Drop Calculations Vol/Number of Drops. 1mL/23Drops =.034mL /drop VII. Conclusion Unlike other labs, this lab allows for the most precise titration. results possible.
to be done. This was to find out what amount of each liquid would be
For this experiment, I will use 30mls of the acid each time and 1gm of
Remove the extra solvent on a steam bath under a hood while flushing the flask with N2 gas, leaving the crude extract. Weigh extract.
of Copper Sulphate. To do this I plan to work out the amount of water
I must use the same amount of enzyme each time I do an experiment so I
Esters.Includes the plant oils, like linalyl acetate which exists in clary sage and lavender. It also includes geranyl acetate which exists in sweet marjoram. Esters has anti-fungal features and used as pain
Esters are organic functional groups formed from the combination of two other functional groups, alcohols and carboxylic acids. One of the hydrogen ion's that are more weakly bonded to the carboxylic acid is released and exchanged for the alkyl group from the alcohol during the reaction which forms the organic salt. This type of ester is the most common and is the one that forms the general structure of the esters (RCOOR') but there are also esters formed from simple hydrocarbon groups. These esters are usually the ones that are known to create the pleasant smells and flavors of fruits, flowers, and food flavorings.
Add the diluent/base liquid or vegetable glycerine. Calculate the amount of diluent needed by subtracting the total amount of liquid already in the bottle (16 +5 = 21 ml) from the total volume of the bottle (50 ml). Therefore, using a clean syringe, add 29 mL of diluent liquid to the bottle. You can also adjust the ratio of the propylene glycol to the vegetable glycerine as desired.