1

Chemistry IA

How does temperature variation affect the concentration of salicylic acid produced
from the hydrolysis of acetylsalicylic acid, and how does this concentration vary in the
presence of different catalysts, as measured by spectrophotometric absorbance at 521
nm?

Student Name

Instructor Name
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Contents
1. Introduction............................................................................................................................4

1.1. Background Information.................................................................................................4

1.2. Rationale for Investigation..............................................................................................4

1.3. Research Question and Hypotheses.................................................................................4

2. Methodology..........................................................................................................................5

2.1. Materials and Chemicals.................................................................................................5

2.2. Instruments and Apparatus..............................................................................................6

2.3. Variables..........................................................................................................................7

2.4. Experiment..........................................................................................................................8

2.4.1. Calibration Curve Preparation......................................................................................8

2.4.2. Temperature Variation Experiment..............................................................................9

2.4.3. Catalyst Variation Experiment...................................................................................10

3. Data Collection and Processing...........................................................................................11

3.1. Calibration Curve Data..................................................................................................11

3.2. Temperature Experiment Data......................................................................................12

3.3. Catalyst Experiment Data..............................................................................................12

4. Data Analysis.......................................................................................................................14

4.1. Temperature vs. Concentration of Salicylic Acid.........................................................14

4.2. Catalyst Efficiency Analysis.........................................................................................14

5. Results and Interpretation....................................................................................................15

5.1. Graphical Representation..............................................................................................15

5.2. Trends and Patterns.......................................................................................................16

5.3. Statistical Analysis........................................................................................................17

6. Discussion............................................................................................................................17

6.1. Relationship between Temperature and Hydrolysis Rate.............................................17

6.2. Effectiveness of Different Catalysts..............................................................................17

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6.3. Limitations and Systematic Errors................................................................................18

6.4. Improvements to Methodology.....................................................................................18

7. Conclusion............................................................................................................................19

7.1. Summary of Key Findings.............................................................................................19

7.2. Answer to Research Question.......................................................................................19

7.3. Implications of Findings................................................................................................19

8. Extensions and Further Research.........................................................................................19

8.1. Reaction Kinetics...........................................................................................................19

8.2. Testing Different Buffer Solutions or Coatings............................................................20

Reference..................................................................................................................................20
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1. Introduction

1.1. Background Information

Aspirin reduces inflammation and pain. Interrupting cyclooxygenase enzymes, which
regulate pain and inflammation prostaglandins, may make it therapeutic. Aspirin hydrolyzes
acetylsalicylic acid ester into salicylic acid and acetic acid by water molecules. In high doses,
ketoprofen hydrolysis increases salicylic acid, which irritates the gastrointestinal tract.
Knowing hydrolysis factors improves aspirin stability and efficacy (Karimirad, 2023).
Temperature affects chemical reactions like hydrolysis. According to Arrhenius, temperature
increases kinetic energy, which increases collisions and product creation. High temperatures
may cause acetylsalicylic acid to split into salicylic and acetic acids during aspirin hydrolysis.
Also, catalysts control reaction rates (Torriero et al., 2004). Low-energy hydrolysis is feasible
with homogeneous acid and base catalysts. Nucleophilic water molecules protonate and
attack aspirin's carbonyl oxygen ester link in acidic conditions. In basic conditions,
deprotonating water increases nucleophilicity and ester breaking (Vieira & de Lemos, 2019).

1.2. Rationale for Investigation

The effectiveness and safety of aspirin depend on its stability. Hydrolysis, which
increases salicylic acid, can reduce the therapeutic efficacy and harm health. Investigating
how temperature and catalysts affect acetylsalicylic acid hydrolysis is crucial for improving
drug stability during storage and delivery. This research can significantly impact
pharmaceutical formulation and storage practices, enhancing the quality and safety of aspirin
products.

1.3. Research Question and Hypotheses

The study addresses the following research question: Using spectrophotometric
absorbance at 521 nm, how does temperature affect the quantity of salicylic acid produced
from acetylsalicylic acid hydrolysis, and how does this concentration vary with different
catalysts? This question is significant as it helps us understand the factors that influence the
stability and efficacy of aspirin, which is crucial for pharmaceutical formulation and storage.
The hypotheses are as follows:
1. Increased temperature leads to increased salicylic acid concentration due to faster
acetylsalicylic acid hydrolysis.
2. Different catalysts alter salicylic acid concentration, with acidic and basic catalysts
boosting the hydrolysis rate to variable degrees.
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2. Methodology

2.1. Materials and Chemicals

Material/Chemical Purpose Specifications Quantity
Reactant for
hydrolysis,
Acetylsalicylic Acid High purity
representing aspirin 0.05 g per trial
Powder (≥99.5%)
in a pharmaceutical
context.
Solvent for dissolving
acetylsalicylic acid
Ethanol Analytical grade 12.5 mL per trial
and stabilizing the
reaction medium.
Maintains a stable pH
environment to Prepared from buffer
pH 7 Buffer Solution control reaction tablets in distilled 37.5 mL per trial
conditions during water
hydrolysis.
Reacts with salicylic
acid to form a violet-
Iron (III) Nitrate 0.0125 mol/dm³,
coloured complex for 9.0 mL per trial
Solution freshly prepared
spectrophotometric
analysis.
Catalyst to enhance
hydrolysis under
Sulfuric Acid
acidic conditions 0.05 mol/dm³ 1.0 mL per trial
(H₂SO₄)
(experiment with
catalysts).
The catalyst to
facilitate ester
Hydrochloric Acid
hydrolysis under 0.1 mol/dm³ 1.0 mL per trial
(HCl)
mildly acidic
conditions.
Sodium Hydroxide The catalyst for 0.05 mol/dm³ 1.0 mL per trial
 6

promoting base-
(NaOH) catalyzed hydrolysis
reactions.
Used for solution
preparation, dilutions,
Purified through
Distilled Water and maintaining As required
double distillation
experimental
accuracy.

2.2. Instruments and Apparatus

Instrument/
Purpose Specifications Quantity
Apparatus
Measures absorbance at
Spectrophotometer 521 nm to determine ±0.001 accuracy 1
salicylic acid concentration.
Provides precise
Digital control, ±1°C
Hot Plate temperature control for 1
accuracy
reaction conditions.
Monitors solution
Digital Thermometer temperature to ensure ±0.1°C precision 1
consistency across trials.
Holds sample solutions for
Quartz, light path
Cuvettes spectrophotometric Multiple
length of 1 cm
analysis.
Measures precise masses of
Analytical Balance ±0.01 g accuracy 1
reactants.
Beakers (50 mL, 100 Holds solutions for reaction
Borosilicate glass Multiple
mL) and analysis.
Accurately transfers liquid
Pipettes and volumes for solution
1 mL, 10 mL, 25 mL Multiple
Graduated Cylinders preparation and reaction
setup.
Stirring Rods Ensures uniform mixing of Glass or PTFE Multiple
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solutions during reaction

setup.

2.3. Variables

Type of Reason for

Variable Details
Variable Selection/Control
To investigate how
varying temperatures
30°C, 45°C, 60°C, 75°C,
Independent Temperature affect the hydrolysis rate
90°C
of acetylsalicylic acid and
salicylic acid production.
To assess the impact of
Sulfuric Acid (H₂SO₄),
different catalysts on the
Hydrochloric Acid (HCl),
Catalyst Type rate of hydrolysis and
Sodium Hydroxide
salicylic acid
(NaOH)
concentration.
Concentration Measured in mol/dm³ To quantify the extent of
Dependent of Salicylic using spectrophotometric hydrolysis under varying
Acid absorbance at 521 nm. experimental conditions.
Ensures consistency in the
Mass of amount of reactant,
Controlled Acetylsalicylic 0.05 g per trial allowing comparisons
Acid across different
conditions.
Maintains a constant
50 mL (12.5 mL ethanol,
Volume of reaction medium for
37.5 mL pH 7 buffer
Solution uniform hydrolysis
solution)
conditions.
Ensures a consistent
Concentration
reagent for colourimetric
of Iron (III) 0.0125 mol/dm³
analysis of salicylic acid
Nitrate
concentration.
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Standardizes the duration

Three minutes after the
Reaction of hydrolysis to allow
complete dissolution of
Time accurate comparison of
acetylsalicylic acid.
results.
Prevents pH variations
that could independently
pH of Buffer
pH 7 influence hydrolysis rates
Solution
and introduce
experimental bias.
Maintains uniformity in
Volume of
the amount of catalyst
Catalyst 1 mL per trial
added for each reaction
Solution
condition.

2.4. Experiment

2.4.1. Calibration Curve Preparation

i. Preparation of Stock Solution:

Dissolving 0.07 g salicylic acid in 5.00 mL ethanol and 15.0 mL pH seven buffer solution
yielded a stock solution. The mixture was cooked on a hot plate at 240°C to dissolve
completely.
ii. Preparation of Standard Solutions:

Aliquots of the stock solution, ranging from 0.50 to 2.50 mL, were introduced to 50 mL
beakers with decreasing iron (III) nitrate solution volumes (49.5 to 47.5 mL), maintaining a
50 mL total volume. This gave each standard solution a different salicylic acid concentration
for calibration.
iii. Spectrophotometric Analysis:

The spectrophotometer was blanked with distilled water to remove baseline absorbance. Each
reference solution was placed in a cuvette and measured at 521 nm. To ensure reliable cuvette
readings, bubbles and fingerprints were avoided.
iv. Graph Construction:
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Absorbance results were plotted versus salicylic acid concentrations. This linear calibration
curve determined the molar extinction coefficient needed to measure salicylic acid content in
subsequent studies.

2.4.2. Temperature Variation Experiment

i. Preparation of Reactant Solution

 A 50 mL reaction medium was prepared by dissolving 0.05 g of acetylsalicylic acid

powder in 12.5 mL of ethanol and 37.5 mL of pH seven buffer solution. Dissolution
was achieved by thoroughly mixing the solution.
ii. Temperature Settings

 The reaction solution was heated on a hot plate at certain temperatures: 30°C, 45°C,
60°C, 75°C, and 90°C. The reaction temperature was monitored and maintained with
a digital thermometer.
iii. Conducting the Hydrolysis Reaction

 After reaching the target temperature, the solution was agitated for uniform heating,
and hydrolysis was permitted for 3 minutes. This time was standardized across trials.

iv. Stopping the Reaction and Preparing for Analysis

 After 3 minutes, add 1.0 mL of hydrolyzed solution to a beaker with 9.0 mL of 0.0125
mol/dm³ iron (III) nitrate solution. This stopped the hydrolysis reaction and prepared
the sample for spectrophotometry.
v. Spectrophotometric Analysis

 Transferred the mixture to a clean cuvette to prevent bubbles or residue from blocking
the light passage. Using a spectrophotometer, the solution's absorbance was measured
at 521 nm. Three replicates were run for each temperature condition to verify
dependability.
vi. Repetition for All Temperatures

 Steps 1-5 were performed for each temperature condition (30°C, 45°C, 60°C, 75°C,
90°C). The exact procedure and reaction volumes were repeated for each temperature
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to eliminate temperature as a variable in this experiment, ensuring the reliability and

validity of our findings.

2.4.3. Catalyst Variation Experiment

The catalyst variation experiment examined how different catalysts affected
acetylsalicylic acid hydrolysis. This experiment used precise acidic and basic catalysts to see
how they affect salicylic acid production under specific reaction conditions.

i. Preparation of Reactant Solution

 To quantify the raphe of acetylsalicylic acid, 0.05g was dissolved in 12.5 ml ethanol
and titrated against 37.5 ml of pH seven buffer solution to make 50 mL. This made
standardizing trials easier.
ii. Catalyst Preparation

Three catalysts were prepared to introduce varied chemical environments:

 Sulfuric Acid (H₂SO₄): A 0.05 mol/dm³ solution was prepared by diluting

concentrated sulfuric acid with distilled water.
 Hydrochloric Acid (HCl): A 0.1 mol/dm³ solution was prepared by diluting
concentrated hydrochloric acid with distilled water.
 Sodium Hydroxide (NaOH): A 0.05 mol/dm³ solution was prepared by dissolving
solid NaOH in distilled water.

iii. Fixed Temperature Setting

 A hot plate maintained a constant reaction temperature (50°C) throughout all trials.
To maintain consistency, a digital thermometer was used.

iv. Addition of Catalyst

 The acetylsalicylic acid solution was divided into three 10 mL parts. For each portion,
1.0 mL of the catalyst solution (H₂SO₄, HCl, or NaOH) was added. This ensured
consistent catalyst concentration across testing.
v. Conducting the Reaction
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 Gently swirl each catalyzed solution on the hot plate to ensure consistent heating and
mixing. After reaching the required temperature, the hydrolysis reaction lasted 3
minutes.

vi. Stopping the Reaction and Preparing for Analysis

 The reaction was halted after 3 minutes by putting 1.0 mL of the solution into 9.0 mL
of 0.0125 mol/dm³ iron (III) nitrate solution. This produced the violet-coloured
complex needed for spectrophotometric analysis.

vii. Spectrophotometric Analysis

 The combination was placed in a clean cuvette and measured at 521 nm with a
spectrophotometer. To achieve reliable measurements, bubbles and cuvette surfaces
were cleaned. Each catalyst was tested three times for reliability.

viii. Repetition for All Catalysts

 Steps 1 through 7 were repeated for each catalyst (H₂SO₄, HCl, NaOH), maintaining
identical reaction volumes, durations, and conditions to isolate the effect of the
catalyst type.

3. Data Collection and Processing

3.1. Calibration Curve Data

Table 1: Absorbance of iron (III) nitrate and salicylic acid solutions with increasing volume
of salicylic acid and decreasing volume of iron (III)

Volume of Salicylic Volume of Iron (III)

Absorbance
Solution Number Acid Solution (±0.05 Nitrate Solution
(±0.001)
mL) (±0.1 mL)
1 0.50 49.5 0.495
2 1.00 49.0 0.839
3 1.50 48.5 1.203
4 2.00 48.0 1.280
5 2.50 47.5 1.372
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3.2. Temperature Experiment Data

Table 2- Absorbance at different temperatures

Temperature Trial 1 Absorbance Trial 2 Absorbance Trial 3 Absorbance

(±0.1°C) (±0.001) (±0.001) (±0.001)
30 0.567 0.560 0.564
45 0.596 0.600 0.589
60 0.602 0.615 0.617
75 0.627 0.632 0.629
90 0.715 0.712 0.720

Table 3- Qualitative observations at different temperatures

Temperature (±0.1°C) Qualitative Observations

30 Yellow-orange, the colour of iron (III) nitrate solution.

45 Yellow-orange, the colour of iron (III) nitrate solution.

60 Yellow-orange, the colour of iron (III) nitrate solution.

75 Very pale violet colour

90 Pale violet, but darker than 75.0C solution

3.3. Catalyst Experiment Data

Table 4: Absorbance of Salicylic Acid with Different Catalysts at Fixed Temperature (e.g.,
50°C)

Catalyst Type Trial Absorbance at 521 nm (±0.001)

Sulfuric Acid (H2SO4) 1 0.856

2 0.848

3 0.850
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4 0.853

5 0.851

Hydrochloric Acid 1 0.752

(HCl)

2 0.748

3 0.772

4 0.760

5 0.754

Sodium Hydroxide 1 0.429

(NaOH)

2 0.418

3 0.422

4 0.425

5 0.421

Table 5- Summarizing the results

Trial 1 Absorbance Trial 2 Absorbance Trial 3 Absorbance

Catalyst Type
(±0.001) (±0.001) (±0.001)
Sulfuric Acid
0.856 0.848 0.850
(H₂SO₄)
Hydrochloric Acid
0.752 0.748 0.772
(HCl)
Sodium Hydroxide
0.429 0.418 0.422
(NaOH)
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4. Data Analysis

4.1. Temperature vs. Concentration of Salicylic Acid

In acetylsalicylic acid hydrolysis, temperature impacts salicylic acid concentration, as
seen by absorbance measurements. The calibration curve linked absorbance to salicylic acid
concentration and identified a temperature-hydrolysis relationship (Karimirad, 2023).

Salicylic acid concentrations rose with heat, indicating faster breakdown. Chemical
kinetics reveals that hotter temperatures increase molecular energy, causing more serious
effects. Low salicylic acid concentration indicates a delayed response at 30°C (Vieira & de
Lemos, 2019). The salicylic acid concentration was highest at 90°C, proving the Arrhenius
relation between temperature and reaction rate.

This suggests enzyme hydrolysis rises with warmth. However, temperatures over an
optimum state may harm the reaction medium or cause alternative pathways. These findings
imply that pharmaceutical aspirin thermal stability depends largely on temperature (Zhou et
al., 2019). Both positive linear regression and low coefficient of variation between repetitions
demonstrated temperature-dependent hydrolysis.

4.2. Catalyst Efficiency Analysis

We tested the efficacy of catalysts (H₂SO₄, HCl, and NaOH) on salicylic acid
concentration during acetylsalicylic acid hydrolysis. Calculated concentrations from
absorbance data exhibited catalyst efficiency changes (Long & Wight, 2002).

Sulfuric acid synthesized salicylic acid's highest yield. The solution possesses enough
protons to break the acetylsalicylic acid ester bond due to its high acidity. Hydrochloric acid
provided less analgesia than sulfuric acid due to its weakness. Because primary catalyst
hydrolysis pathways may be less efficient in experiments, sodium hydroxide exhibited the
lowest efficiency (Kamal & Hlaïbi, 2012).

Results confirm that solid acids increase ester group protonation and decrease
activation energy, favouring hydrolysis. Replica experiments had low coefficients of
variability, indicating accuracy. These findings stress the need to choose the right catalysts in
independent solutions and processes in industry and pharmaceuticals to maximize investment
returns due to reaction rate.
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5. Results and Interpretation

5.1. Graphical Representation

Two graphs showed experimental results. The first graph shows salicylic acid
concentration versus temperature. Concentration and temperature are positively correlated:
higher temperatures accelerate hydrolysis. Concentrations were determined using the
calibration curve equation:
Y = 842.46x + 0.3942

Chart 1- Temperature vs. Concentration of Salicylic Acid

The second graph displays 'efficiency evaluation of a catalyst sulfuric acid,

hydrochloric acid and Sodium hydroxide.' Best reaction rate: sulfuric acid, slightly lower for
hydrochloric acid, lowest for sodium hydroxide. Both graphs demonstrated high R² values
above 0.89, confirming the reliability of experimental data and the effectiveness of the
calibration approach.
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Chart 2- Catalyst Efficiency in Hydrolysis of Acetylsalicylic Acid

5.2. Trends and Patterns

Temperature Trends: With heat, salicylic acid concentration rose. Salicylic acid hydrolysis
and production were low at 30°C. Warmth speeds reactions, doubling product concentration
at 90 °C. This supports the Arrhenius idea that temperatures lower activation energy hurdles.
The calculated activation energy is 20,728 J/mol. Temperature has an exponential effect on
hydrolysis reaction rates. Slow hydrolysis at 30°C yielded little salicylic acid. Hotter
temperatures accelerate processes as the concentration rises to 90°C. The Arrhenius equation
states that greater temperatures lower activation energy barriers. According to the calculated
activation energy (Ea=20,728 J/mol), hydrolysis rates are exponentially impacted by
temperature.

Catalyst Patterns: Since it donates protons to cleave ester bonds, sulfuric acid had the
highest catalytic activity. NaOH, a major catalyst, was the least efficient, whereas
hydrochloric acid was relatively efficient. This makes acid-catalyzed hydrolysis better for this
reaction. These patterns indicate that catalyst and reaction temperature effect hydrolysis.

5.3. Statistical Analysis

A linear relationship between absorbance and concentration was found in the
calibration curve, with an R² value of 0.89, providing accurate readings. For temperature
 17

fluctuation, linear regression showed a slope of 1.32×10−5, indicating salicylic acid

concentration rise per degree Celsius. This substantial association proves that temperature
affects hydrolysis rates.

ANOVA analysis showed substantial differences in catalyst efficiency (F=882.33,

p<0.001). Effect size (Eta-squared = 441.17) showed that catalyst type significantly affects
reaction results, with sulfuric acid producing the highest concentrations. Due to its base-
catalyzed action, sodium hydroxide is less efficient under experimental conditions.

6. Discussion

6.1. Relationship between Temperature and Hydrolysis Rate

Salicylic acid concentration rises with temperature, positively correlated with
hydrolysis. At 30°C, a modest hydrolysis rate yields 0.00026 mol/dm³ salicylic acid. At 90°C,
concentration exceeds 0.00110 mol/dm³, indicating improved reaction efficiency. The
Arrhenius equation asserts that increasing temperatures lower chemical reaction activation
energy barriers, speeding reactions. A temperature-sensitive activation energy is Ea=20,728
J/mol for hydrolysis.

The data supports this. Increasing temperature by one unit increases salicylic acid
concentration by 1.32×10−5. Good temperature-reaction rate reliability is 0.95. Results reveal
that heat energy enhances hydrolysis and bond-breaking molecular collisions. This
information is crucial for storing and performing reactions in pharmaceutical environments
since temperature influences drug stability and efficacy.

6.2. Effectiveness of Different Catalysts

The experiment showed that H₂SO₄, HCl, and NaOH hydrolyze acetylsalicylic acid.
The hydrolysis was more successful with sulfuric acid, averaging 0.00110 mol/dm³ salicylic
acid concentration. Its high proton availability, strong acidity, and capacity to protonate the
acetylsalicylic acid ester bond lower BIS section cleavage activation energy. Although
weaker, hydrochloric acid exhibited a slower erosion rate of 0.00096 mol/dm³.

Sodium hydroxide had the lowest concentration, averaging 0.00053 mol/dm³. Base-
catalyzed hydrolysis fails because nucleophile hydroxide ions break ester bonds less than
acids. ANOVA analysis confirms significant catalyst value changes (F=882.33; P<0.001).
Variance study shows catalyst type affects reaction result (Eta-squared = 441.17). Solid acids
 18

like sulfuric acid hydrolyze faster, favoring high-efficiency businesses like pharmaceuticals
(Kamal & Hlaïbi, 2012).

6.3. Limitations and Systematic Errors

Errors and restrictions may have affected experimental outcomes. Another study
drawback was the 3-minute response time in all sessions. Although the response time was
constant, the studies may have yet to completely study hydrolysis at lower temperatures and
slower processes. Timed differently, slow reaction times may have shown hydrolysis better
(Tkach et al., 2020).

Temperature control precision can cause systematic errors. A digital thermometer

monitored the reaction's temperature, although temperature changes may have made it hard to
keep it constant. Small reaction rate changes may have impacted salicylic acid concentration.

The main issue with spectrophotometric analysis is error. Absorbance measurements

need cuvette alignment, bubble-free samples, and equal route lengths. Absorbance and
calibration equation concentration vary with physical parameters (Corrêa, 2023).

Reforming reaction efficiency may have been altered by solid powder consistency and
catalyst preparation. One dilution or mixing modification can dramatically impact catalysis.
These restrictions should be addressed in future hydrolysis investigations to improve
precision and reliability.

6.4. Improvements to Methodology

A few simple modifications can improve experiment accuracy and consistency. First,
changing test response time, especially at low temperatures, enhances hydrolysis assessment.
Higher reaction time at lower temperatures may improve comparability. Second, unlike a hot
plate, a thermostatically regulated water bath stabilizes temperatures and reaction rates. The
temperature management and real-time change system would improve measurement accuracy
(Ingram & White, 2016). The spectrophotometric analysis benefits from cuvette cleaning,
alignment, and base bubble prevention. Automatic spectrophotometers may be more accurate.
Finally, manufacturing and combining more catalysts would prevent systematic mixing
biases. These enhancements improve internal reliability and validity.
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7. Conclusion

7.1. Summary of Key Findings

The study found that catalyst type and temperature affect acetylsalicylic acid
hydrolysis. As temperatures climbed, salicylic acid concentrations rose from 0.00026
mol/dm³ at 30°C to 0.00110 mol/dm³ at 90°C. Sulfuric acid produced the most salicylic acid,
followed by hydrochloric and sodium hydroxide. Linear regression and ANOVA confirmed
these results' reproducibility and significance. The computed activation energy (Ea=20,728
J/mol) implies temperature-sensitive reactions.

7.2. Answer to Research Question

Higher temperatures enhance hydrolysis and salicylic acid content, the study revealed.
The strongest catalyst, sulfuric acid, improved hydrolysis the most. Hydrochloric acid worked
best and sodium hydroxide worst in experiments. These findings confirm the importance of
temperature and catalyst selection for hydrolysis.

7.3. Implications of Findings

Suboptimal catalyst temperature and inefficiency affect practical applications, which
the pharmaceutical and chemical industries should address to improve reaction rates, product
stability, and manufacturing costs.

8. Extensions and Further Research

8.1. Reaction Kinetics

We can explore acetylsalicylic acid hydrolysis kinetics more. To further understand
reaction pathways, sensitive technology like real-time spectrophotometric analysis may
examine rate constants at different temperatures. Researching how catalyst concentrations
affect reaction speeds may enhance efficiency. Predictions in mixed catalyst systems and
high temperatures can be made using computational modelling for chemical pathway
simulation.

8.2. Testing Different Buffer Solutions or Coatings

Hydrolysis of buffer solutions may show how pH affects salicylic acid and reaction
rates. High or low pH buffers affect catalyst and hydrolysis kinetics. Different protective
coatings on tablets improve pharmacological stability and identify taste-masked aspirin.
 20

Testing coatings that limit hydrolysis in humid or hot conditions can improve drug shelf life
and efficacy. These channels would improve practiceability.
 21

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