aayushman ee final

Aayushman S. Goyal/Extended Essay/The Shri Ram School /002227-0001 1

Extended Essay Title: Investigating the effect of ultrasound waves on the equilibrium constant of an esterification reaction. Research question: How do ultrasound waves affect the value of equilibrium constants of the esterification reactions between ethanoic acid and five different alcohols (methanol, ethanol, propan-2-ol, butan-1-ol, pentan-2-ol) of increasing alkyl chain lengths? Subject: Chemistry Session: May 2014 Candidate Name: Aayushman Sahuwala Goyal Candidate Number: 002227-0001 School Name: The Shri Ram School, Moulsari School Code: 002227 Supervisor Name: Dr. Sriparna Chakrabarti Word Count: 3987 words

2 Aayushman S. Goyal/Extended Essay/The Shri Ram School /002227-0001

Abstract: Esters are an interesting class of organic compounds for their characteristic ‘fruity odour’ and various industrial applications. A new emerging, environment-friendly technique – sonication was used in esterification to increase the yield of esters. My research question is: “How do ultrasound waves affect the value of equilibrium constants of the esterification reactions between ethanoic acid and five different alcohols (methanol, ethanol, propan-2-ol, butan-1-ol, pentan-2-ol) of increasing alkyl chain lengths?” I have used 1 moldm-3 of aqueous solutions of five alcohols with increasing alkyl chain lengths (C1 to C5) and esterified with 1 moldm-3 of ethanoic acid using 1 moldm-3 of H2SO4 as catalyst. I had first conducted the esterification reactions by heating the alcohol-carboxylic acid mixture in a water bath at 90-100°C for 30 minutes. The resultant mixtures were titrated with 1 mol dm-3 of NaOH solution. It was observed that due to the high temperature of the water bath and the low boiling points of some of the alcohols, the esters were not formed properly. Hence I repeated the same experiment by refluxing the reaction mixtures for one hour. Another set of esterification was done by using ultrasound waves of frequency 40 kHz in an ultrasonic bath at an ambient temperature 55-60°C for 30 minutes. Also, the volume of 1 moldm-3 NaOH solution required to neutralize 1 moldm-3 H2SO4 catalyst was eliminated from the final titre values for accuracy in the Kc values. The equilibrium constants of all these esterification reactions were computed and compared. I concluded that the Kc values of esterification done by sonication were significantly higher than those done by refluxing. My hypothesis that sonication would increase the yield of esters produced at that particular temperature was accepted. Interestingly, refluxing gave the maximum yield of ethyl ethanoate whereas sonication gave the maximum yield of 1-methylbutyl ethanoate. Word Count: 299 words


Table of contents: Heading Page no. Introduction:

x Approach to the research question x Background research

How sonicators work? x Plan of Action

4 4 6 6 7

Investigation: x Experiment 1 x Experiment 2 x Experiment 3 x Experiment 4

10 11 15 18 22

Conclusion 25 Evaluation 27 Future Scope 27 Appendices

x Appendix 1: Apparatus x Appendix 2: Detailed calculations

28 28 29

Bibliography 32 Acknowledgements 35


Introduction Approach to the research question: Organic chemistry is the science of designing, synthesizing, and developing applications for molecules that contain carbon.1 After being introduced to this field in my tenth standard, I have had a strong inclination towards Organic Chemistry and particularly, esters due to their role in perfumes and flavourings industry. Made by condensation reaction between alcohols and carboxylic acids, esters are known for their characteristic fruity odour, causing them to have a wide range of uses. For example, 1-methylbutyl ethanoate (from pentan-2-ol + ethanoic acid) is claimed to be the primary flavouring agent in ‘Juicy Fruit’ chewing gum.2 Some practical applications of esters are their use in Plexiglas (a solid transparent plastic) and Dacron (a polyester fiber) requiring large-scale production of long chain esters.3 With the advances in technology, there are newer, better and more cost effective ways to carry out production of esters.4 Literature Search: During literature search, I found that esterification is one of the widely studied reactions. I was looking for a new alternative technique to carry out the esterification reaction.5 Some of the methods pursued by other scholarly research groups were the use of polymer chemistry in the synthesis of esters6 and the use of microwave irradiation7. 1 “Is all around us.” Organic Chemistry. Web. 16 Dec. 2013. http://www.acs.org/content/acs/en/careers/whatchemistsdo/careers/organic-chemistry.htcm3 2 “Honey Bees, Whiskey and Juicy Fruit Gum.” Smells Like Science. Web. 16 Dec. 2013. http://smellslikescience.com/honey-bees-whiskey-and-juicy-fruit-gum/

3 "Esters in Nature and Society." Esters in Nature and Society. N.p., n.d. Web. 02 Feb.

2014. <http://personal.ashland.edu/~bmohney/ket_scholars/esters.html>. 4 “ESTERIFICATION.” Esterification. Web. 20 Dec. 2013. http://vigoschools.org/~mmc3/AP%20Chemistry/ap%20lab%20documents/Esterfication.pdf 5 Manohar, Basude, Vangala R. Reddy, and Benjaram M. Reddy."Esterification by ZrO2 and Mo-ZrO2 eco-friendly solid acid catalysts." Synthetic communications 28.17 (1998): 3183-3187. 6 Theato, P. (2008), Synthesis of well-defined polymeric activated esters. J. Polym. Sci. A Polym. Chem., 46: 6677–6687. 7 Loupy, André, et al. "The synthesis of esters under microwave irradiation using dry-media conditions." Canadian Journal of chemistry 71.1 (1993): 90-95.

http://www.acs.org/content/acs/en/careers/whatchemistsdo/careers/organic-chemistry.html

http://www.acs.org/content/acs/en/careers/whatchemistsdo/careers/organic-chemistry.html

http://smellslikescience.com/honey-bees-whiskey-and-juicy-fruit-gum/

http://vigoschools.org/~mmc3/AP%20Chemistry/ap%20lab%20documents/Esterfication.pdf



Sonication8 - an emerging technique in the frontiers of science could be extended to esterification, though esters are traditionally made by refluxing acid and alcohol in presence of acid catalyst. The beauty of esterification is that we can use a wide range of combination between various carboxylic acids and alcohols to carry out our studies. So I decided to find out whether conducting esterification reactions using ultrasonic waves affect the equilibrium constants of the reactions and hence affect the yield of the esters; I also wanted to investigate the effect of sonication on esters of varying alkyl chain lengths. This led me to the research question: How do ultrasound waves affect the value of equilibrium constants of the esterification reactions between ethanoic acid and five different alcohols (methanol, ethanol, propan-2-ol, butan-1-ol, pentan-2-ol) of increasing alkyl chain lengths? An esterification reaction takes place when an alcohol and a carboxylic acid condense in the presence of a catalyst (usually sulphuric acid) to yield the corresponding ester and water. For example: C2H5OH + CH3COOH CH3COOC2H5 + H2O (alcohol + carboxylic acid ester + water) The compounds in the above reaction are ethanol, ethanoic acid, ethyl ethanoate and water respectively. The ‘ ’ symbol is used as the process of esterification is a reversible reaction and a dynamic equilibrium is established between the reactants and products after the reaction is allowed to rest for some time. Dynamic equilibrium is that state of chemical equilibrium where the forward and backward reactions occur at the same rate.9 According to Le Chatelier’s Principle (“If a change is made to the conditions of chemical equilibrium, then the position of equilibrium will readjust so as to minimize the change made”)10

8 “Esters. An Introduction.” Ester. Web. 20 Dec. 2013. http://www.chem.umass.edu/~samal/269/ester.pdf 9 John Green and Sadru Damji. IB Chemistry, Third Edition. Victoria: IBID Press, 2007. Print. (Page 181) 10 John Green and Sadru Damji. IB Chemistry, Third Edition. Victoria: IBID Press, 2007. Print. (Page 185)

http://www.chem.umass.edu/~samal/269/ester.pdf


The equilibrium constant (Kc) of a reaction can be defined as the product of the concentration of the products divided by the product of the concentration of the reactants.11 Its expression is: Kc = [ester][water] [acid][alcohol], Since in dilute aqueous solutions, the concentration of water would not change from its initial concentration, the expression for Kc can be simplified to: Kc = [ester] as [water] is constant in dilute solutions [acid][alcohol] Higher the Kc value, more the reaction goes to forward direction and higher the yield of ester. Since altering certain reaction conditions could shift the position of equilibrium towards the forward direction, the yield of esters can be improved. Hence finding the equilibrium constant and investigating the effect of carrying out the reaction using ultrasound waves on its Kc was worthy of investigation. Sonication is cost-effective as less use of fossil fuels was required since the process was done under ambient temperature. Background Research: How do sonicators work? An ultrasound refers to any sound that occurs beyond the frequency range of human hearing - frequency of over 20,000 Hz. The most familiar use of an ultrasound is to see the image of a baby in its womb. For medical purposes, the ultrasound is sent through the required part of the body, and it bounces off dense surfaces (the child in the womb) to give a gray image.12 An ultrasound is most commonly used as an ultrasonic cleaner used to clean objects such as spectacles or jewelry. Ultrasonic cleaners can also be used to clean oils off cars and weapons for federal agents. Sonication can also be used to improve sterilization and influence the development of living cells in food.13 The process of cleaning through ultrasound is simple; the object to be cleaned is placed in a detergent solution of water inside the cleaning tank and sound waves (greater than 20,000 Hz) are carried through the solution in a pattern that varies between two phases; the high-pressure phase and the low-pressure phase. In the 11 John Green and Sadru Damji. IB Chemistry, Third Edition. Victoria: IBID Press, 2007. Print. (Page 184) 12 “What is an Ultrasound?”. MNT. Web. 20 Dec. 2013. http://www.medicalnewstoday.com/articles/245491.php 13 "The Uses of Ultrasound in Food Technology." The Uses of Ultrasound in Food Technology. N.p., n.d. Web. 03 Feb. 2014. <http://www.sciencedirect.com/science/article/pii/S135041779600034x>.

http://www.medicalnewstoday.com/articles/245491.php


low-pressure phase, many tiny bubbles or cavities form and start sticking to the object (cavitation). In the high-pressure phase, these bubbles implode, giving out large amounts of energy that attacks the surface of the object, thereby cleaning it.14 This principle is applied in chemical reactions, the electrons in the reactant molecules get excited as the imploding cavities attack the outside of the reaction vessel, initiating the reaction and leading to effective collisions, thus lowering the activation energy of the reaction. It is more environmentally friendly than other chemical cleaners and it is more efficient as it uses less water, energy and time to clean an object.15 One major breakthrough with ultrasound is its use in the production of bio-diesel. It was found that bio-diesel can now be processed faster due to ultrasound-assisted reactors.16 Plan of Action: I had planned to investigate sonication is more effective in the production of esters, compared to the refluxing method. To make the investigation more general to maximum kinds of esters, I had planned to study the esterification between ethanoic acid and five different alcohols with increasing carbon chain lengths. The alcohols chosen are methanol (carbon-1), ethanol (carbon-2), propan-2-ol (carbon-3), butan-1-ol (carbon-4) and pentan-2-ol (carbon-5) due to their ready availability in the lab and because they are successive members in the homologous series (C1-C5) of alcohols. I had chosen ethanoic acid as the carboxylic acid due to its easy availability, low cost and wide availability in natural fruit and flavours.17 1 mol dm-3 of sulphuric acid was used in this reaction as a catalyst and a dehydrating agent. As a catalyst it lowers the activation energy of the reaction for both forward and backward directions, speeding up the reaction; however that would not increase the yield of esters. As a dehydrating agent, it removes the water produced in the reaction, shifting the position of equilibrium forward. Some important details of the five alcohols used for my study are mentioned in Table 1 below:

14 “How to use your ultrasonic cleaning system.” Tuttnauer. Web. 20 Dec. 2013. http://www.tuttnauerusa.com/sites/default/files/assets-usa/support/Ultrasonic-CSU-Manual.pdf 15 "Five Advantages of Ultrasonic Cleaning." Five Advantages of Ultrasonic Cleaning. N.p., n.d. Web. 03 Feb. 2014. <http://www.iultrasonic.com/frequently-asked-questions/five-advantages-of-ultrasonic-cleaning.html>. 16 “Faster Biodiesel Processing with Ultrasound-Assisted Reactors”. Uidaho. N.p. n.d. Web. 08 Feb. 2014. http://web.cals.uidaho.edu/biodiesel/files/2012/11/ultrasonic.pdf 17 "Esters in Nature and Society." Esters in Nature and Society. N.p., n.d. Web. 02 Feb. 2014. <http://personal.ashland.edu/~bmohney/ket_scholars/esters.html>.

http://www.tuttnauerusa.com/sites/default/files/assets-usa/support/Ultrasonic-CSU-Manual.pdf



Table 1: Structural formulae and boiling points of alcohols under study IUPAC Names (A-E)

No. of carbon atoms

Structural formulae Boiling Point18,19,20

Methanol: A

1

21

64.7qC

Ethanol: B

2

22

78.4qC

Propan-2-ol: C

3

23

82.5qC

Butan-1-ol: D

4

24

117.4°C

Pentan-2-ol: E

5

25

119.3°C

18 "SmartLearner." SmartLearner. N.p., n.d. Web. 09 Feb. 2014. <http://www.smartlearner.mobi/science/videopastpapers/organics/organics_1.htm>. 19 N.p., n.d. Web. 09 Feb. 2014. <http://avogadro.chem.iastate.edu/MSDS/Propan-2-ol.htm>. 20 "Pentan-2-ol." 6032-29-7|pentan-2-ol|sec-amyl Alcohol. N.p., n.d. Web. 09 Feb. 2014. <http://en.chembase.cn/substance-168826.html>. 21 "Revision Systems, Inc." Revision Systems Inc. N.p., n.d. Web. 10 Feb. 2014. <http://revision-systems.co.uk/exam-boards/aqa/chemistry-alcohols-carboxylic-acids-and-esters/>. 22 "." Representing Organic Structures. N.p., n.d. Web. 10 Feb. 2014. <http://firstyear.chem.usyd.edu.au/prelab/organic_structures.shtml>. 23 "Unit 1 - Elaborations - Structural Formulas." UWEC. N.p., n.d. Web. 09 Feb. 2014. <http://www.chem.uwec.edu/Chem150_S07/elaborations/unit1/unit1-d-structural-formulas.html>. 24 "Creative Chemistry Molecular Models." Creative Chemistry Positional Isomers. N.p., n.d. Web. 10 Feb. 2014. <http://www.creative-chemistry.org.uk/molecules/positional.htm>.


My hypothesis: The collision theory of kinetics states that a reaction takes place when the energy of collisions exceeds the activation energy of the reaction (the minimum amount of energy required for the reaction to occur). The sulphuric acid molecules will collide with the water molecules produced more effectively due to the cavitation effect of sonication, removing the water molecules (as addition complex) more efficiently and that in turn will shift the position of equilibrium to the right, increasing the concentration of esters formed. So the Kc of the esterification reaction conducted in the sonicator would be higher than that produced by refluxing the mixture of reactants. If I keep the initial concentrations of ethanoic acid and the respective alcohols the same, formation of more esters will lead to a higher value of Kc. As the physical properties of esters change when the length of alkyl chain is changed ultrasound waves would have different effect on the Kc of esterification for esters with varying alkyl chain lengths. 25 "GCSE CHEMISTRY - What Are the Isomers of Pentanol?" GCSE Science. N.p., n.d. Web. 10 Feb. 2014. <http://www.gcsescience.com/o39.htm>.


Investigation I have conducted esterification reactions between 1 mol dm-3 of ethanoic acid and 1 mol dm-3 alcohols A-E (Table 1) using 1 mol dm-3 H2SO4 as catalyst under three different reaction conditions. In Experiment 1, the alcohol-carboxylic acid reaction mixture was heated in a water bath at 100 °C for 30 minutes; in Experiment 3 the reaction mixture was refluxed using a heating mantle for 1 hour and in Experiment 4, the reaction mixture was sonicated using an ultrasonic bath at 55-60 °C. The esterified reaction mixtures were allowed to reach equilibrium and then titrated against standard NaOH solutions. From these titre values, the unknown concentration of un-reacted acid could be found and having known the initial concentrations of ethanoic acid and the alcohols, the concentrations of other components at equilibrium and thus the equilibrium constants (Kc) of each ester could be computed using the following expression for equilibrium constant: Kc = [ester] [acid][alcohol] Temperature was kept constant as Kc is a constant at a particular temperature only. Therefore the five esters that were going to be produced were: methyl ethanoate (from methanol), ethyl ethanoate (from ethanol), 1-methylethyl ethanoate (from propan-2-ol), butyl ethanoate (from butan-1-ol) and 1-methylbutyl ethanoate (from pentan-2-ol) respectively. In Experiment 2, I computed the correction values for 1 mol dm-3 of H2SO4 catalyst. NaOH will react with the un-reacted acetic acid in the reaction mixture and H2SO4 catalyst will also neutralize NaOH, so we had to eliminate that volume from our titre values. Titrations of alcohol-carboxylic acid reaction mixtures were performed before and after adding requisite volume of H2SO4. The difference in the titre values were recorded. The five esterification reactions are: (Alcohol used) 1. CH3OH (aq) + CH3COOH (aq) CH3COOCH3 (aq) + H2O (l) (Methanol) 2. C2H5OH (aq) + CH3COOH (aq) CH3COOC2H5 (aq) + H2O (l) (Ethanol) 3. C3H7OH (aq) + CH3COOH (aq) CH3COOC3H7 (aq) + H2O (l) (Propan-2-

ol) 4. C4H9OH (aq) + CH3COOH (aq) CH3COOC4H9 (aq) + H2O (l) (Butan-1-

ol) 5. C5H11OH (aq) + CH3COOH (aq) CH3COOC5H11 (aq) + H2O (l) (Pentan-

2-ol)


The variables for experiments 1, 3 and 4 are: Independent variable: Using five different alcohols with increasing carbon chain lengths (C1-C5). Dependent variable: The equilibrium constant (Kc) of the reaction at the particular temperature. Controlled variables: Variables such as concentration and volume of the reactants and catalyst were maintained at all times. Duration of the reaction and temperature of the reaction were also maintained throughout. Experiment 1: Aim: To determine the equilibrium constant of the esterification reaction between ethanoic acid and the alcohols A-E using 1 mol dm-3 sulphuric acid as catalyst by heating the reaction mixtures in water bath at 90-100 °C. For experiments 1, 3 and 4: 1. I had prepared 1 mol dm-3 of the following compounds using the dilution

method. The volume of each compound in 1 mol dm-3 of solution is: 12.01 cm3 of ethanoic acid in 200 cm3 distilled water 6.4 cm3 of methanol in 200 cm3 distilled water 9.2 cm3 of ethanol in 200 cm3 distilled water 12.0 cm3 of propan-2-ol in 200 cm3 distilled water 14.8 cm3 of butan-1-ol in 200 cm3 distilled water 17.6 cm3 of in 200 cm3 – Pentan-2-ol 1.0 cm3 in 20 cm3 – Sulphuric acid 2. After pouring 200 cm3 of ethanoic acid solution, 200 cm3 of the respective

alcohol solution and 20 cm3 of 1 mol dm-3 sulphuric acid into a 500 cm3 beaker, I stirred the solution till it became homogenous.

Methodology:

x I placed the respective solutions into the water bath at a temperature of 90-100°C for half an hour.

x I removed the respective solution from the water bath, covered the top of the beaker with foil and let the reaction mixture rest for one week.

x After one week, I took 3 titrations of 10 cm3 of each solution using 1 mol dm-3 NaOH solution and phenolphthalein as an indicator.

It was observed that butan-1-ol and pentan-2-ol form a separate layer over the water, which shows that as you go up in the homologous series of alcohols, solubility decreases. It was also interesting to note some of the smells of the


esters. 1-Methylbutyl ethanoate gave off smell of bananas and ethyl ethanoate gave off a smell of nail polish remover. Data Collection: Temperature of the lab: 23 °C. Titre values – Water bath Table 2: Methyl ethanoate – Methanol + ethanoic acid Initial volume -

cm3 (r0.05)

Final volume - cm3

(r0.05) Difference in volume - cm3

(r0.10) 1. 0.00 5.80 5.80 2. 5.80 11.40 5.60 3. 11.40 17.00 5.60 Table 3: Ethyl ethanoate – Ethanol + ethanoic acid Initial volume -

cm3 (r0.05) Final volume - cm3


(r0.10) 1. 0.00 5.50 5.50 2. 5.50 11.40 5.90 3. 11.40 17.30 5.90 Table 4: 1-Methylethyl ethanoate – Propan-2-ol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 5.40 5.40 2. 5.40 11.00 5.60 3. 11.00 16.60 5.60 Table 5: Butyl ethanoate – Butan-1-ol + ethanoic acid

Table 6: 1-Methylbutyl ethanoate – Pentan-2-ol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 2.80 2.80 2. 2.80 6.00 3.20 3. 6.00 9.20 3.20

Initial volume - cm3 (r0.05)

Final volume - cm3


(r0.10) 1. 0.00 2.60 2.60 2. 2.60 6.00 3.40 3. 6.00 9.40 3.40


Table 7: Summary of the titre values of esters formed by water bath method Name of Ester (Alcohols A-E) Volume of 1 mol dm-3 NaOH required

for neutrlisation of reaction mixtures - cm3 (r0.05)

Methyl ethanoate (A) 5.60

Ethyl ethanoate (B) 5.90

1-Methylethyl ethanoate (C) 5.60

Butyl ethanoate (D) 3.40

1-Methylbutyl ethanoate (E) 3.20

Data Processing: Before calculating equilibrium constant (Kc), a series of steps must be followed26:

1. The number of moles of base must be found. As we know, c = n/v (Concentration = Number of moles/ volume) so n = c x v. Concentration is in (mol dm-3) and volume (Titre value) will be in dm-3 so it has to be converted from cm3 to dm-3. This can be done so by dividing the value by 1,000.

2. The number of moles of acid must be found. This can be done so by multiplying the number of moles of base with the ratio of the co-efficients of the acid and the base (Always 1:1 in this case).

3. The concentration of acid can now be found. As mentioned in step 1, c = n/v. Therefore the concentration of acid = number of moles/volume of acid used (In dm-3 again). From here the equilibrium constant can be found. If the value of step 3 is (1-x) mol dm-3, then the concentration of un-reacted acid = x mol dm-3. The concentration of un-reacted alcohol will also be the same, and the concentration of the ester formed shall be = (1 – x) mol dm-3. 27 So the formula for Kc that we can use is:

26 “Titration of Hydrochloric Acid with Sodium Hydroxide”. Austin Peay State University Department of Chemistry. Web. 23 Dec. 2013. https://www.apsu.edu/sites/apsu.edu/files/chemistry/SP12_1011_Titration_of_Hydrochloric_Acid_with_Sodium_Hydroxide_0.pdf 27 Please see appendix 2 for detailed calculations.

https://www.apsu.edu/sites/apsu.edu/files/chemistry/SP12_1011_Titration_of_Hydrochloric_Acid_with_Sodium_Hydroxide_0.pdf



Kc = (1-x) mol dm-3 (x)2 mol dm-3 To simplify the formula above, our units for Kc will always be in dm3/mol in this case. x is to the power of 2 because the concentration of acid and alcohol at equilibrium will be the same. To further simplify the steps above, x = Titre value/10. So the following values of Kc for the esters were: Table 8: Equilibrium constant values of esters formed by water bath method Name of ester (Alcohols A-E)

Titre value/10 = (x) cm3

Kc= (1-x)/(x)2 Kc value (dm3/mol)

Methyl ethanoate (A)

5.60/10 = 0.56 (1-0.56)/(0.56)2 1.40

Ethyl ethanoate (B)

5.90/10 = 0.59 (1-0.59)/(0.59)2 1.17

1-Methylethyl ethanoate (C)

5.60/10 = 0.56 (1-0.56)/(0.56)2 1.40

Butyl ethanoate (D)

3.40/10 = 0.34 (1-0.34)/(0.34)2 5.71

1-Methylbutyl ethanoate (E)

3.20/10 = 0.32 (1-0.32)/(0.32)2 6.64

Results and Discussion: As we can see, the Kc values for esters made from alcohols D and E are significantly higher than those made from alcohols A-C. This is because the lower alcohols with lesser number of carbon atoms (A-C) have low boiling points and were more volatile, and hence I had realized from the high titre values and the low Kc values that esterification reaction did not take place at all for lower alcohols as at that temperature (90-100 °C), the alcohols (boiling points of 64.7, 78.4 and 82.5 °C for A-C respectively) evaporated from the reaction mixture leaving more acid content. I had also realized that 1 mol dm-3 sulphuric acid in the mixture was not accounted for during titration. This must not be included in the titre values as it was not a reactant in the reaction but simply a catalyst. Therefore I set out to make corrections and exclude the volume of NaOH used to neutralise 1 cm3 sulphuric acid from the recorded titre values.


Experiment 2: Aim: To determine the volume of 1 mol dm-3 sodium hydroxide solution required to neutralize 1 cm3 of 1 mol dm-3 sulphuric acid catalyst that needs to be accounted for while calculating the titre values and to make corrections in the titre values for 1 mol dm-3 sulphuric acid. Methodology: x After mixing 200 cm3 of ethanoic acid solution with 200 cm3 of alcohol

solution in a 500 cm3 beaker, I stirred the solution till it became homogenous.

x I titrated 10 cm3 of the solution with 1 mol dm-3 of NaOH using phenolphthalein as an indicator.

x After noting down those titre values, I added the 20 cm3 of 1 mol dm-3 of

sulphuric acid to the solution, stirred well to make the solution homogeneous and then carried out three titrations again.

x The difference is the volume of 1 mol dm-3 sodium hydroxide solution

required to neutralize 1 mol dm-3 sulphuric acid catalyst which had to be subtracted from the titrations of the esterification reactions.

Data Collection: Temperature of the lab: 20.5 °C Titre values before sulphuric acid was added Table 9: Methyl ethanoate – Methanol + ethanoic acid Initial volume -

cm3 (r0.05) Final volume - cm3 (r0.05)

Difference in volume - cm3 (r0.10)

1. 0.00 4.80 4.80 2. 4.80 9.60 4.80 3. 9.60 14.30 4.70 Table 10: Ethyl ethanoate – Ethanol + ethanoic acid Initial volume -



1. 0.00 5.50 5.50 2. 5.50 11.30 5.80 3. 11.30 17.10 5.80


Table 11: 1-Methylethyl ethanoate – Propan-2-ol + ethanoic acid Initial volume -



1. 0.00 6.30 6.30 2. 6.30 12.60 6.30 3. 12.60 19.00 6.40 Table 12: Butyl ethanoate – Butan-1-ol + ethanoic acid Initial volume -



1. 0.00 5.40 5.40 2. 5.40 10.90 5.50 3. 10.90 16.40 5.50 Table 13: 1-Methylbutyl ethanoate – Pentan-2-ol + ethanoic acid Initial volume -



1. 0.00 5.50 5.50 2. 5.50 11.00 5.50 3. 11.00 16.60 5.60 Table 14: Summary of the titre values of alcohol-acid mixtures before adding 1 mol dm-3 sulphuric acid Name of alcohol + acid (Alcohols A-E) Volume of 1 mol dm-3 NaOH required

for neutralisation of reaction mixtures before adding acid catalyst - cm3

(r0.05) Methyl ethanoate (A) 4.80 Ethyl ethanoate (B) 5.80 1-Methylethyl ethanoate (C) 6.30 Butyl ethanoate (D) 5.50 1-Methylbutyl ethanoate (E) 5.50

Titre values after 1 mol dm-3 sulphuric acid was added Table 15: Methyl ethanoate – Methanol + ethanoic acid Initial volume -



1. 0.00 5.40 5.40 2. 5.40 11.10 5.70 3. 11.10 16.50 5.40


Table 16: Ethyl ethanoate – Ethanol + ethanoic acid Initial volume -



1. 0.00 5.90 5.90 2. 5.90 11.90 6.00 3. 11.90 17.90 6.00 Table 17: 1-Methylethyl ethanoate – Propan-2-ol + ethanoic acid Initial volume -



1. 0.00 6.60 6.60 2. 6.60 13.20 6.60 3. 13.20 19.70 6.50 Table 18: Butyl ethanoate – Butan-1-ol + ethanoic acid Initial volume -






1. 0.00 6.10 6.10 2. 6.10 12.20 6.10 3. 12.20 18.20 6.00 Table 20: Summary of the titre values of alcohol-acid mixtures after adding 1 mol dm-3 sulphuric acid Name of Ester (Alcohols A-E) Volume of 1 mol dm-3 NaOH required

for neutrlisation of reaction mixtures

- cm3 (r0.05) Methyl ethanoate (A) 5.40 Ethyl ethanoate (B) 6.00 1-Methylethyl ethanoate (C) 6.60 Butyl ethanoate (D) 5.80 1-Methylbutyl ethanoate (E) 6.10


Data Processing: Table 21: Difference between both sets of titre values of alcohol-acid mixtures Name of Ester (Alcohols A-E)

Value 1 (before adding catalyst) - cm3

(r0.05)

Value 2 (after adding catalyst) - cm3 (r0.05)

Value 3 (Difference) - cm3

(r0.10)

Methyl ethanoate (A) 4.80 5.40 5.40 – 4.80= 0.60 Ethyl ethanoate (B) 5.80 6.00 6.00 – 5.80 = 0.20 1-Methylethyl ethanoate (C)

6.30 6.60 6.60 – 6.30 = 0.30

Butyl ethanoate (D) 5.50 5.80 5.80 – 5.50 = 0.30 1-Methylbutyl ethanoate (E)

5.50 6.10 6.10 – 5.50 = 0.60

Results and Discussion: The values found in Table 6 (value 3) for each alcohol-acid mixture tell us that the next time we take titre values of esters, the amounts given above must be subtracted from the titre value in order to give us a more accurate equilibrium constant value. However, the problem with the alcohols evaporating and not being present in the final reaction mixture still had to be dealt with. This is what led me to experiment 3. Experiment 3: Aim: To determine the equilibrium constant of the esterification reaction between ethanoic acid and the alcohols A-E using 1 mol dm-3 sulphuric acid as a catalyst by refluxing the reaction mixtures for one hour. In order to avoid the evaporation of low boiling alcohols and to ensure a complete esterification reaction, I needed to use a new, more efficient method, refluxing the reaction mixtures using heating mantle and a Soxhlet apparatus. The main role of reflux is to react compounds through constant vaporisation and condensation. As this is taking place the reactants are reacting to produce the ester. The main advantage of using a reflux setup over a water bath setup is that the temperature does not go beyond the boiling point of the mixture. It simply gets vaporised and then condenses back down to the flask. Therefore this would give me a more reliable value of equilibrium constant, which could be compared with that of sonication later. I had not allowed the refluxed solutions to stand for a week but only allowed them to come to room temperature before titration as it was assumed that the solutions produced by using reflux for one hour had already reached equilibrium.


Methodology:

x I transferred the prepared alcohol-acid reaction mixture to a round bottom flask that was attached to the Soxhlet apparatus using grease and cardboard pieces (for secured clamping) (as shown in the photo below).

Figure 1: Reflux setup for Esterification

x It can be seen that the heating mantle at the bottom is connected to the plug point has been set to a temperature of 80qC. The condenser Soxhlet apparatus on the top has an inlet that is connected to the spout of the tap and an outlet that leads to the sink. The round bottom flask that contains the reaction mixture is at the bottom of the setup and placed on the heating mantle. A few boiling chips consisting of pieces of broken porcelain have been added to the round bottom flask to prevent any damage that could be done to the apparatus and to keep the boiling solution from bumping.28

x After refluxing all the solutions for one hour, I removed the solution from the setup, allowed to come down to the room temperature and took 3 titrations of 10 cm3 of each solution using 1 mol dm-3 NaOH and phenolphthalein as an indicator.

Data Collection: Temperature of the lab: 16 °C Titre values – Reflux Table 22: Methyl ethanoate – Methanol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 6.90 6.90 2. 6.90 16.90 10.00 3. 16.90 23.80 6.90

28 “Refluxing.” The Organic Chemistry Undergraduate Laboratories. Web. 23 Dec. 2013. http://www.chem.wisc.edu/areas/organic/orglab/tech/reflux.htm

http://www.chem.wisc.edu/areas/organic/orglab/tech/reflux.htm


Table 23: Ethyl ethanoate – Ethanol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 5.70 5.70 2. 5.70 11.30 5.60 3. 11.30 17.00 5.70 Table 24: 1-Methylethyl ethanoate – Propan-2-ol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 7.10 7.10 2. 7.10 14.20 7.10 3. 14.20 21.50 7.30 Table 25: Butyl ethanoate – Butan-1-ol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 6.50 6.50 2. 6.50 12.90 6.40 3. 12.90 19.40 6.50 Table 26: 1-Methylbutyl ethanoate – Pentan-2-ol + ethanoic acid Initial volume -



(r0.10) 1. 0.00 7.30 7.30 2. 7.30 14.60 7.30 3. 14.60 21.80 7.20 Table 27: Summary of the titre values of esters formed by reflux method Name of Ester (Alcohols A-E) Volume of 1 mol dm-3 NaOH required

for neutralization of reaction mixtures - cm3 (r0.05)

Methyl ethanoate (A) 6.90

Ethyl ethanoate (B) 5.70 1-Methylethyl ethanoate (C) 7.10 Butyl ethanoate (D) 6.50 1-Methylbutyl ethanoate (E) 7.30


Table 28: Volume of NaOH solution required to neutralize reaction mixtures after correction for sulphuric acid catalyst Name of Ester (Alcohols A-E)

Old titre value - cm3 (r0.05)

Volume to subtract (from table 6) - cm3

(r0.05)

Difference = volume of 1 mol dm-3 NaOH required to neutralize esterified reaction mixtures - cm3

(r0.10) Methyl ethanoate (A)

6.90 0.60 6.90 – 0.60 = 6.30

Ethyl ethanoate (B) 5.70 0.20 5.70 – 0.2 = 5.50 1-Methylethyl ethanoate (C)

7.10 0.30 7.10 – 0.3= 6.80

Butyl ethanoate (D) 6.50 0.30 6.50 – 0.30 = 6.20 1-Methylbutyl ethanoate (E)

7.30 0.60 7.30 – 0.60 = 6.70

Data Processing: Table 29: Equilibrium constant values of esters formed by reflux method Name of Ester (Alcohols A-E)

Titre value/10 = (x) - cm3

Kc = (1-x)/(x)2 Kc value (dm3/mol)


6.30/10 = 0.63 (1-0.63)/(0.63)2 0.93

Ethyl ethanoate (B)

5.50/10 = 0.55 (1-0.55)/(0.55)2 1.49


6.80/10 = 0.68 (1-0.68)/(0.68)2 0.69

Butyl ethanoate (D)

6.20/10 = 0.62 (1-0.62)/(0.62)2 0.98


6.70/10 = 0.67 (1-0.67)/(0.67)2 0.73

Results and Discussion: As we can see from the Kc values given above in Table 9 and the titre values in Table 7, although the titre values were considerably high, the Kc values provide for a better analysis as there is consistency of values this time. With the water bath, there were two extremes of Kc values found. The only issue that might have been faced was that since the reflux produced solutions were not given time to rest, it is questioned whether the equilibrium constant might have been higher had they been given one week or even 24 hours to rest. This could have been verified by taking a set of titrations one week after the reflux reaction was carried out.


Experiment 4: Aim: To determine the equilibrium constant of the esterification reaction between ethanoic acid and the alcohols A-E using 1 mol dm-3 sulphuric acid as catalyst by using a sonicator bath. Methodology:

x I transferred the prepared alcohol-acid reaction mixture to a 250 cm3 conical flask that was partially immersed into the 40 kHz sonicator bath through a clamp stand (as shown in the photo below). A cardboard piece was also used to ensure that the flask did not fall into the bath. The following set up was used:

Figure 2: Ultrasound setup for esterification – outside

Figure 3: Ultrasound setup for esterification – inside


x I placed the respective solution into the sonicator bath filled with water

set at 55-60qC and allowed the reaction to take place using ultrasound waves of frequency of over 20,000 Hz for half an hour.

x The sonicator used was the LMUC-2A Ultrasonic cleaner made by Lab Man Scientific Instruments PVT. LTD.

x Its ultrasonic frequency was 40 kHz or 40,000 Hz.

x It was observed during the reaction as seen in figure 3 that small bubbles (cavities) were forming and coming closer to the flask.

x After half an hour, I removed the respective solution from the sonicator bath, covered the top of the beaker with foil and let the esterified reaction mixture rest for one week.

x After one week, I took 3 titrations of 10 cm3 of each solution using 1 mol dm-3 NaOH and phenolphthalein as an indicator.

Data Collection: Temperature of the lab: 22 °C Titre values – Ultrasound Table 30: Methyl ethanoate – Methanol + ethanoic acid Initial volume -



1. 0.00 5.10 5.10 2. 5.10 10.30 5.20 3. 10.30 15.50 5.20 Table 31: Ethyl ethanoate – Ethanol + ethanoic acid Initial volume -



1. 0.00 5.10 5.10 2. 5.10 10.20 5.10 3. 10.20 15.40 5.20 Table 32: 1-Methylethyl ethanoate – Propan-2-ol + ethanoic acid Initial volume -



1. 0.00 5.00 5.00 2. 5.00 10.00 5.00 3. 10.00 15.20 5.20


Table 33: Butyl ethanoate – Butan-1-ol + ethanoic acid Initial volume -






1. 0.00 4.10 4.10 2. 4.10 8.30 4.20 3. 8.30 12.50 4.20 Table 35: Summary of the titre values of esters formed by ultrasound method Name of Ester (Alcohols A-E) Volume of 1 mol dm-3 NaOH

required for neutralization of reaction mixtures - cm3 (r0.05)

Methyl ethanoate (A) 5.20 Ethyl ethanoate (B) 5.10

1-Methylethyl ethanoate (C) 5.00

Butyl ethanoate (D) 5.20

1-Methylbutyl ethanoate (E) 4.20

Table 36: Volume of NaOH solution required to neutralize reaction mixtures after correction for sulphuric acid catalyst Name of Ester (Alcohols A-E)

Old titre value - cm3 (r0.05)

Volume to subtract (from table 6) - cm3

(r0.05)

Difference = volume of 1 mol dm-3 NaOH required to neutralize esterified reaction mixtures - cm3

(r0.10) Methyl ethanoate (A)

5.20 0.60 5.20 – 0.60 = 4.60

Ethyl ethanoate (B)

5.10 0.20 5.10 – 0.20 = 4.90


5.00 0.30 5.00 – 0.30 = 4.70

Butyl ethanoate (D)

5.20 0.30 5.20 – 0.30 = 4.90


4.20 0.60 4.20 – 0.60 = 3.60


Data Processing: Table 37: Equilibrium constant values of esters formed by ultrasound method Name of Ester (Alcohols A-E)

Titre value/10 = (x) - cm3

Kc = (1-x)/(x)2 Kc value (dm3/mol)


4.60/10 = 0.46 (1-0.46)/(0.46)2 2.55

Ethyl ethanoate (B)

4.90/10 = 0.49 (1-0.49)/(0.49)2 2.12


4.70/10 = 0.47 (1-0.47)/(0.47)2 2.40

Butyl ethanoate (D)

4.90/10 = 0.49 (1-0.49)/(0.49)2 2.12


3.60/10 = 0.36 (1-0.36)/(0.36)2 4.94

Results and Discussion: As we can see from the Kc values given above in Table 37 and the titre values given in Table 36, the ultrasound method has given a greater yield of esters in terms of concentration. The only issue during this reaction might have been that the speed of the reaction. Since the temperature was low and the flask was not completely immersed into the bath, the reaction might not have reached completion after half an hour. However, the reaction mixture was allowed to reach equilibrium for one week. Conclusion Table 38: Comparison of the two sets of Kc values (Reflux and Ultrasound) Name of Ester (Alcohols A-E)

Kc value - Reflux (dm3/mol)

Kc value - Ultrasound (dm3/mol)

Methyl ethanoate (A) 0.93 2.55

Ethyl ethanoate (B) 1.49 2.12


0.69 2.40

Butyl ethanoate (D) 0.98 2.12


0.73 4.94

The table above shows different Kc for esterification reactions by refluxing and sonication. The titre values suggest that esterification has taken place. The titre values of refluxing method are higher which seems to suggest that the reaction has not reached completion and the low Kc of their respective esters agree with it. Since the titre values are high, the unreacted acid content will probably be


high, hence the yield of esters will be less. According to my hypothesis, the Kc of the esters produced by sonicator should be higher and this proved correct as the Kc values of sonicator were higher than those produced by refluxing. This proves that the sonicator is a more effective approach to esterification as it improves the yield of esters. Can any pattern be detected from the Kc values of esters of varying alkyl chain lengths (A-E)?

Figure 4: Comparison of Kc values of all 3 reactions Looking at figure 4, it can be inferred that varying alkyl chain lengths do not cause Kc values to increase or decrease in a gradual manner. The Kc remains unaffected for the lower alcohols A-C and remains the same under any reaction condition. However, for high boiling and less soluble higher alcohols D and E, sonication even at ambient temperature, resulted in greater yield of esters, also high temperature in water bath has allowed these reaction mixtures to go further towards formation of esters as compared to refluxing. In case of ultrasound and water bath, 1-methylbutyl ethanoate was produced in higher yields whereas in case of refluxing, ethyl ethanoate gave the maximum yield. Although the Kc for the first 3 esterifications using water bath are low, the last two are even higher than those of the ultrasound-assisted esterification. This could be because the temperature of the water bath was high at 90-100°C so this caused the forward reaction to occur faster when the alcohols did not evaporate (butan-1-ol, pentan-2-ol) and so their Kc values came out higher.

01234567

A (C1) B (C2) C (C3) D (C4) E (C5)

Kc

valu

es

Esters of varying alkyl chain lengths

Comparison of Kc values of all 3 reactions

Water Bath

Reflux

Ultrasound


Evaluation How reliable was my data?

x In case of water bath, the volume of 1 mol dm-3 NaOH required to neutralize the sulphuric acid in the solution was not subtracted from the values before calculating Kc.

x In case of reflux, the solutions were not allowed to rest for a week before calculating Kc.

x In case of ultrasound, a high temperature was not used for the reaction, a

medium temperature of 55-60°C was used.

x Since the temperature of the lab varied during the time of the reactions, this might have caused the Kc values to change according to temperature. For instance, the Kc values of esters produced by reflux could be lower than expected since the temperature of the lab recorded at that time was the lowest of the 4 experiments.

Therefore comparing the three sets of Kc values without controlling all the variables impacted my conclusion. How reliable are the secondary sources? While looking for ways to calculate Kc, I got misled by an article in Austin Peay State University’s “Titration of Hydrochloric Acid with Sodium Hydroxide”.29 In page 3 of the document what it refers as ‘initial concentration of acid’, I actually found this value to be ‘concentration of acid reacted’. Sometimes web resources confuse us and do not provide authentic information. Future Scope: I had set out to determine how effective the use of ultrasound was in the formation of esters. From the equilibrium constant values measured, it is clear that the use of ultrasound gives better yield of esters as compared to the traditional refluxing. The use of ultrasound in esterification is cost effective and could positively impact companies and their costs of production all around the world. Besides esterification, sonication can be extended to so many industrially important chemical reactions to not only enhance speed but also produce greater yields of products, at the same time using lesser toxic materials and lesser fuel usage. 29 “Titration of Hydrochloric Acid with Sodium Hydroxide”. Austin Peay State University Department of Chemistry. Web. 23 Dec. 2013. https://www.apsu.edu/sites/apsu.edu/files/chemistry/SP12_1011_Titration_of_Hydrochloric_Acid_with_Sodium_Hydroxide_0.pdf




Appendices: Appendix 1: Materials and Apparatus used:

x 500 cm3 Beaker x 200 cm3 Beaker x 150 cm3 Conical flask x 250 cm3 Round bottom flask x Dropper x 1000 cm3 Measuring cylinder x 200 cm3 Measuring cylinder x 100 cm3 Measuring cylinder x 50 cm3 Measuring cylinder x 10 cm3 Measuring cylinder x Pipette x Pipette Pump x Burette x Clamp stand x Boiling chip x Cardboard pieces x Stirrer x Latex Gloves x Water Bath x Sonicator Bath x Reflux apparatus x Foil

Chemicals used:

x ethanoic acid x Methanol x Ethanol x Propan-2-ol x Butan-1-ol x Pentan-2-ol x 1 mol dm-3 Sulphuric acid x Distilled water x Phenolphthalein x Sodium Hydroxide x Grease


Appendix 2: Detailed calculations for finding Kc: When produced by reflux:

1. Methyl ethanoate – Moles of NaOH = 1 mol dm-3 x 6.3/1000 dm3= 0.0063 mol of NaOH. Moles of CH3COOH = 0.0063 mol x 1/1 = 0.0063 mol of CH3COOH. Conc. of CH3COOH = 0.0063 mol/(10/1000) dm3= 0.63 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.63)/0.632 = 0.93 dm3/mol.

2. Ethyl ethanoate – Moles of NaOH = 1mol dm-3 x 5.5/1000 dm3= 0.0055 mol of NaOH. Moles of CH3COOH = 0.0055 mol x 1/1 = 0.0055 mol of CH3COOH. Conc. of CH3COOH = 0.0055 mol/(10/1000) dm3= 0.55 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.55)/0.552 = 1.49 dm3/mol.

3. 1-Methylethyl ethanoate – Moles of NaOH = 1mol dm-3 x 6.8/1000 dm3= 0.0069 mol of NaOH. Moles of CH3COOH = 0.0068 mol x 1/1 = 0.0068 mol of CH3COOH. Conc. of CH3COOH = 0.0068 mol/(10/1000) dm3= 0.68 mol dm-3 of CH3COOH.

Therefore the Kc = (1 - 0.68)/0.682 = 0.69 dm3/mol.

4. Butyl ethanoate – Moles of NaOH = 1mol dm-3 x 6.2/1000 dm3= 0.0062 mol of NaOH. Moles of CH3COOH = 0.0062 mol x 1/1 = 0.0062 mol of CH3COOH. Conc. of CH3COOH = 0.0062 mol/(10/1000) dm3= 0.62 mol dm-3 of CH3COOH.


5. 1-Methylbutyl ethanoate –


Moles of NaOH = 1mol dm-3 x 6.7/1000 dm3= 0.0067 mol of NaOH. Moles of CH3COOH = 0.0067 mol x 1/1 = 0.0067 mol of CH3COOH. Conc. of CH3COOH = 0.0067 mol/(10/1000) dm3= 0.67 mol dm-3 of CH3COOH.


When produced by sonicator: 1. Methyl ethanoate –

Moles of NaOH = 1mol dm-3 x 4.6/1000 dm3= 0.0046 mol of NaOH. Moles of CH3COOH = 0.0046 mol x 1/1 = 0.0046 mol of CH3COOH. Conc. of CH3COOH = 0.0046 mol/(10/1000) dm3= 0.46 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.46)/0.462 = 2.55 dm3/mol.

2. Ethyl ethanoate – Moles of NaOH = 1mol dm-3 x 4.9/1000 dm3= 0.0049 mol of NaOH. Moles of CH3COOH = 0.0049 mol x 1/1 = 0.0049 mol of CH3COOH. Conc. of CH3COOH = 0.0049 mol/(10/1000) dm3= 0.49 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.49)/0.492 = 2.12 dm3/mol.

3. 1-Methylethyl ethanoate – Moles of NaOH = 1mol dm-3 x 4.7/1000 dm3= 0.0047 mol of NaOH. Moles of CH3COOH = 0.0047 mol x 1/1 = 0.0047 mol of CH3COOH. Conc. of CH3COOH = 0.0047 mol/(10/1000) dm3= 0.47 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.47)/0.472 = 2.40 dm3/mol.

4. Butyl ethanoate – Moles of NaOH = 1mol dm-3 x 4.9/1000 dm3= 0.0049 mol of NaOH. Moles of CH3COOH = 0.0049 mol x 1/1 = 0.0049 mol of CH3COOH. Conc. of CH3COOH = 0.0049 mol/(10/1000) dm3= 0.49 mol dm-3 of CH3COOH.



5. 1-Methylbutyl ethanoate – Moles of NaOH = 1mol dm-3 x 3.6/1000 dm3= 0.0036 mol of NaOH. Moles of CH3COOH = 0.0036 mol x 1/1 = 0.0036 mol of CH3COOH. Conc. of CH3COOH = 0.0036 mol/(10/1000) dm3= 0.36 mol dm-3 of CH3COOH. Therefore the Kc = (1 - 0.36)/0.362 = 4.94 dm3/mol.


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Acknowledgements I would like to acknowledge the assistance and support of the following people:

x Dr. Sriparna Chakrabarti, Supervisor and Chemistry Teacher x Mr. Vijay Sharma, Laboratory Technician x Ms. Manisha Malhotra, Principal x Ms. Anjali Sharma, Extended Essay and IB Co-ordinator x Ms. Anuradha Goyal, Mother x Mr. Vinay Goyal, Father x Mr. Arpit Goyal, Brother

aayushman ee final

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