Which Antacid is The Most Effective?
Stage 2 Chemistry
Mr T
Sace: 701102E
Part A : Deconstruct Which Antacid is the most effective?
Background Information:
pH: pH is a quantitative measurement of the Acidic/Basic nature of an aqueous solution, in which the
value of hydrogen ions per liter equivalent are measured on a logarithmic scale between 1 and 10−14
grams equivalents per litre, between 0 and 14, where a pH of less than 7 is acidic, and greater than 7 is
alkaline1. The pH scale is shown below in figure 1.1.
Figure 1.1: The pH scale 2
What is an Antacid?
Antacid is an inclusive consumer term for weak Alkaline substances that are used primarily to
treat the symptoms of ​gastroesophageal reflux disease​ and indigestion​. Antacids are used to
increase the PH condition of the Gastrointestinal tract as to reduce the symptoms of acidic
condition.stomach acid conventionally isat a pH between 1.5-3.5. Antacids can be purchased
without a prescription and generally comes in three forms of solute; Being Powdered, liquid or
capsulated form.
Antacids are generally composed of two or more alkalizing components such as: Aluminium Hydroxide,
Sodium bicarbonate, magnesium hydroxide or calcium carbonate. They act in Increasing the PH of the
Gastrointestinal tract by undergoing a neutralisation reaction with stomach acid (hydrochloric acid) (HCl)
to reduce both the concentration of H + ions and the volume of acidic solution within the stomach. In
turn temporarily relieving the symptoms of an overly acidic stomach.
The Antacids investigated in this instance will be Mylanta, Gastro Health antacid capsule and Zantac
Effectiveness Defined:
Effectiveness is the measure of the positive impact of the substance while limiting negative impacts, in
the instance of antacids, the measurable positive impact is the Neutralising power of the Alkaline
substance which is measured by the increase of the pH value of the solution, where the greater the PH
1
2
​(A. Schreiber, 2020)
​(Acids and bases: 8.31 - The pH scale, 2018)
of the solution the less amount of hydronium ( H + ) ions are present. The Acid Neutralising capacity
(ANC) is therefore the measure of the effectiveness.
Negative impacts:
In regards to negative impacts, there are three major adverse impacts of antacid treatments which are
associated with the antacid used in treating. Being gastral, Metabolic Alkalosis and Metal toxicity .As
Antacids are generally combinations of two or more alkaline compounds neutralisation of adverse
effects between compounds generally occur, However some key factors must be considered when
treating patients.
Gastral:
When treatment occurs with a carbonate compound such as calcium carbonate, the reaction between
calcium carbonate and Hydrochlroic acid, the product in the acid base reaction will be carbon dioxide
( C O2 ) , calcium chloride( C aCl2 ) and water ( H 2 O ), as seen below in figure 1.2. While this reaction is
effective in two aspects, being the neutralising of the Acid resulting in the formation of the metallic salt,
and the dilution of the solution by having precipitate water, the production of carbon dioxide within the
stomach results in flatulence resulting in abdominal discomfort.
Figure 1.2: General Gastral production
H Cl + CaC03 → C O2 + C aCl + H 2O
Metabolic Alkalosis
Alkalosis occurs when the saturation of Bicarbonate ( HCO− 3 ) ions disrupts the balance of H + ions
within the gastrointestinal tract, as the stomach exists in a general state of acidosis, alkalosis has serious
adverse effects on the gastrointestinal tract. When in an alkaline state, the enzyme Pepsin in the body
fails to be activated, and the digestion of protein is halted, additionally, the Parietal cells in the stomach
that are responsible for secreting hydrochloric acid work in an accelerated state so that the stomach can
return to acidic condition, resulting in cellular damage.
Metal Toxicity
As all of the antacid compounds are composed of Alkali metal based solutions, the presence of increased
levels of metallic ions ( M g +2 , Al+3 , C a+2 , E tc..) within the gastrointestinal tract have a large impact on
the digestinartory processes of the body. An example of an adverse effect by metal saturation is that of
Magnesium, when present in excess in the gastrointestinal tract, it induces contracts in the smooth
muscles, resulting in an increased rate of peristalsis; resulting in decreased digestion and Diarrhea in
patients.Adverse Aluminum acts in contracting the smooth muscles resulting in the opposite effect.
Ultimately, the primary aim of this investigation is to trial three antacids to measure the effectiveness of
antacids, a series of analytical chemistry practicals must be undergone to yield a result that considers all
factors:
1) PH
2) Rate of reaction
3) Cost
4) Adverse effects
Titration:
To investigate the molarity of the antacids,The process of titration will be undergone. The neutralising
effects of the antacids will be compared using acid-base titration, the analyte in this case will be the
aqueous antacid and the titrant will be the hydrochloric acid of known molarity. The indicator, methyl
orange is amphoteric in nature, when in an acidic condition will be observable as red, and when in an
acidic condition will be yellow as seen below in figure 1.3.​(3)
Figure 1.3: Titration diagram
Aim:
The aim of the experiment is to determine the effectiveness of three antacids (Mylanta,Gastro health
capsule & Zantac), furthermore to determine the most effective commercial antacid in treating
indigestion.
Hypothesis:
As The capsulated Pill(Gastro-health) is protected by a less reactive coating during the digestion period,
its contained alkaline substance will be of the highest concentration.As the capsulated compound does
not need to interact with the pre-gastrointestinal tract, it will homogenize best into solution, resulting
in the greatest ANC and highest measured molarity.
3
​(Warren, 2020)
Table 1.4 :Variables For Antacid Titration.
Dependent
Independent
Controlled
uncontrolled
The titer value and in turn
the molarity of the antacid.
The brand of Antacid,
and hence the
concentration of
alkaline compounds
within each of the
brands and their
neutralising ability.
The dilution of the alkenes
into solution
The hegemony of the titre solutions in
distilled water
The molarity of
hydrochloric acid used in
titration
The temperature/ pressure of the room
the variation of
alkaline compound
used allows for the
dependent variable
to be effected, which
then yields a result
that has a
measurable impact
towards the
hypothesis
to insure the results
gathered in the experiment
are of high validity, all
variables other than the
antacid used must remain
constant
the dependent variable of
alkalinity and neutralising
effect the antacid is in
regards to the independent
variable of the brand used,
it is hypothesised that the
capsulised antacid will be
the most effective.
As the antacids underwent crushing, they
were in a powdered condition, as the
solutions are designed to be ingested
straight into the gastrointestinal tract
many have hydrophobic functional groups
and are non homogeneous in neutral
conditions, hence the rate at which active
collision in the acid base titration are
impacted and the equilibrium value is less
valid, additionally, the maccerated antacid
solutions are likely to have a varied density
to that of water, and the majority of the
solution would rise to the surface of the
buret or sink to the head decreasing the
accuracy and hence the validity of the
results.
Table 1.5: Risk Assessment Of Antacid Titration.
Risk
Mitigation
PPE
Hydrochloric Acid -Combustible/Corrosive
(Eye/Skin damage)
Avoid swirling solution without caution, actively
avoid direct contact with the acidic substances
and avoid open flames or sparks while
handing the acid (as H+ Ions are extremely
combustible)
Safety glasses, lab coats and rubber
gloves must be worn at all times.
Reaction gas precipitate-
Avoid direct inhalation of gasses from reaction,
as chronic gas and carbon dioxide are
possible precipitates in many reactions
Safety glasses, lab coats and rubber
gloves must be worn at all times.
Glass Shards- sharp (cuts/ abrasions)
Practice caution around all glassware,
particularly in the cleaning process, where
glass becomes slippery and the highest risk is
present.
Safety goggles, lab coat, protective
footwear.
Waste solution- possible acidic solution
To mitigate the risk associated with the
formation of alternate (hazzardous)
compounds within the conical flask/ waste
solution( H 2 O + C O2 → H 2 CO3 ) the waste
solution should be handled with caution and
direct contact should be avoided.
Safety goggles, lab coat, protective
footwear.
Ethical Consideration:
In the process of titration, the use of ​ hydrochloric acid, methyl orange and the basic solutions
must be done ethically, as hydrochloric acid, methyl orange and the basic solutions could
impact water PH levels and in tern if not managed correctly, could be of great detriment by
contaminating water supply, resulting in the harming of aquatic life or impact to flora and fauna.
Additionally the ingestion of the test solution will not occur over the course of the practical,
avoiding the ethical considerations of unrequited drug consumption.
Table 1.6: Material list and effects on data of Antacid Titration.
●
●
●
●
●
●
●
●
●
●
●
●
●
●
Material list:
3x branded antacids with known active
ingredients
Weight boat
Mortar and pestle
Glass funnel
Distilled water
3x 250ml volumetric flask
3x volumetric pipet (10ml)
1L 0.2mol Hydrochlroic acid solution
Electric scale
Burret (100ml)
Conical flask(100ml)
Methyl orange solution
Boss head/ clamp
Retort stand
Effects on data:
-if the active ingredients are unknown, the
adverse effects and other characteristics would
be unknown, and hence the validity of the
results would be inconclusive and the data
would be less significant.
-for all measuring instruments, if faulty,
reactants and products could be measured
inaccurately, decreasing the accuracy and
validity of the results by creating systematic
errors.
-if the value of the concentration of
hydrochloric acid solution is incorrect, the
experimental accuracy would be reduced.
Table 1.7: Method & Justification of Antacid Titration.
(method must be Conducted once for Each Antacid solution)
Method
Justification
1)
-
-
Read the dosing for antacid, and measure the weight
of the cumulative dosage prior to maceration,
recording the mass in proposed table 7
2) Complete a thorough rinse of all titration equipment
with appropriate solutions (hydrochloric acid solution of
same molarity in conical flask, titter in buret, etc.)
placing the recommended dosage into a mortar, using a pestle,
maccerate the pills into a fine powder and return to weigh boat,
recording the weight in proposed table 7
3) Usinging a (250mL) volumetric flask and distilled
water, dilute the dosage into a 250mL aqueous
solution and homogenize the solution.
4) Using a volumetric pipet, pipet 10ml of 0.2mol
Hydrochloric acid solution into the conical flask (In
reference to figure 1.2: Titration diagram), using a
seperate pipet, drop approximately three drop of
methyl orange solution into the conical flask (solution
should appear red.
In reference to figure 1.2, fill the Buret with the Titrant until the
level reading is above zero, rinse the solution through the head
of the buret, and insure the level represented is accurate.
In reference to figure 1.2, complete titration, ensuring to stop
when the solution transitions to orange. Record the value in
proposed table 8 titer results:
5) Repeat step four three times per antacid, recording the
results in each instance.
-
-
By crushing the capsules, the surface area of the
alekenic substances increase, based on collision
theory, increasing the likelihood of active collision
and increasing both the solubility of the solution in
the water and the active collision rate in reaction
Using a volumetric pipet ensures that the volume of
solution is accurate across each trial, increasing the
validity of the results.
Completing three trials allows for the formation of
averages and for trials of high variation to be
excluded from the results, hence limiting the impact
of random errors.
Chemical Compounds :
Table 1.8: Quantitative & Qualitative Properties of hydrochloric acid & methyl orange
Hydrochloric Acid( H Cl) :
aqueous hydrogen chloride gas that is transparent.
Concentration 2mol/L
4
Methyl Orange (C 14 H 15 N 3 O3 SN a) :
Amphoteric indicator compound that is red in acidic conditions (pH 3.2) and yellow in alkenic condition (pH 4.4),
hence orange in neutral conditions and indicating when aqueous solution is neutral.
5
4
5
​(HCl - Wolfram|Alpha, 2020)
​(methyl orange - Wolfram|Alpha, 2020)
Table 1.9: Quantitative & Qualitative Properties of antacids and there components
Contents (active)
Mylanta
GastroHealth
Zantac
-Calcium Carbonate(550mg)
- Magnesium hydroxide
(110mg)
-Calcium
Carbonate(228.23mg)
- Magnesium oxide
(41.75mg)
Ranitidine Hydrochloride
(168mg)
Contents (inactive)
(discarded Glucose
capsule)
Weight uncrushed (per
recommended dosage)
(3.4g)
(3g)
(9g)
Weight crushed (per
recommended dosage)
(3.4g)
(2.6g)
Large discrepancy due
to discernment of
capsule.
(9g)
Observation
-
White coloured solution
Flocculating and
sedimentary particles
observable in solution
-
White coloured
solution
Strong
homogenisation
Absence of
suspended
particles
-
Yellow Tinged solution
Flocculating and
sedimentary particles
observable in solution
Results:
Proposed table 1.1.0: masses of Antacid prior to Titration
Name
Mylanta
GastroHealth
Zantac
Mass (uncrushed)
Mass (crushed)
Variation and
cause/impact
Proposed table(s) 8: Titration Results:
Calcium carbonate and magnesium hydroxide:
C aCO3 + 2HCl → C aCl2 + CO2 + H 2 O
M g(OH)2 + 2HCl → M gCl2 + 2H 2 O
Brand name
Titer one
Titer two
Titer Three
average
Titer two
Titer Three
average
Mylanta
Calcium carbonate and Magnesium oxide:
C aCO3 + 2HCl → C aCl2 + Co2 + H 2 O
M gO + 2HCl → M gCl2 + H 2 O
Brand name
Titer one
Gastro Health
Ranitidine Hydrochloride:
C 13 H 23 CIN 4 O3 S + H Cl → C 13 H 23 CIN 4 O3 S(HCl) (non-imidazole blocker of histamine receptors
(parietal glands)
Brand name
Titer one
Titer two
Titer Three
average
Type of Antacid Titer one
Titer two
Titer Three
average
Zantac
Condensed:
Mylanta
Gastro Health
Zantac
Part C: Complete Practical Report
Aim:
The aim of the experiment is to determine the effectiveness of three antacids (Mylanta,Gastro health
capsule & Zantac) in regards to their alkalinity, furthermore to determine the most effective commercial
antacid in treating indigestion. And to compare values from the manufacturer as stated on the label to
values extrapelled via analytical chemistry.
Chemical Concepts:
The process of titration constitutes an acid base reaction of a solution of known
concentration (analyt) with a solution of unknown concentration(titrant) in the presence
of an indicator. The volume of point at which the neutralisation of the reaction occurs is
then recorded (by observable colour change) and after three trials, an average value is
calculated and hence the molarity of the contents of the reaction can be calculated.
In regards to the indicator, as the amine functional groups interact with H + ions the
polarity of the indicator can change, resulting in a structural isomer in which the colour
of the solution changes.​The indicator used in the practical is Methyl Orange, which is an
amphoteric substance that is Orange in Ph below 3.2, and yellow above 4.4, and hence
orange in the window of 3.2-4.4. Range, making it ideal for a weak base titration strong
acid titration, as the pH indicator range is on slightly more acidic than neutral condition,
this is a possible source of error.
Based on the ​Brønsted-Lowry theory, acids are compounds in which donates protons
and hence is referred to as a conjugate base, while a base accepts protons and is
hence a conjugate acid.
In the process of neutralisation reaction, the alkinic substance will oxidise the proton
H + ions in solution, resulting in the formation of covalent hydroxides ( OH − ) . as more
hydroxides are formed in solution, the number of aqueous H + ions will decrease, and
hence the substance will reduce it’s availability of donating hydrogen, and the solution
will become more basic.
As the alkaline substances (Antacids) are designed to oxidise Stomach acid, the acid in
which the antacids will be oxidising is hydrochloric acid (HCl) of low molarity.
Hydrochloric acid is a polar compound comprised of a singular hydrogen bonded to a
chlorine atom through a singular pi bond in an aqueous water solution, hydrogen
chloride is a monoprotic acid (it can only ionize a single time) the hydrogen is of slight
positivity, and interacts with the water molecules to produce a hydronium ion, as shown
below in figure 2.1. And hence the hydrochloric acid solution is governed by le
chatelier's principle, in which as the system shifts to neutralise in the reactions with the
antacids, the system will act to counteract change, shifting to produce more hydronium
ions until all of the hydrochloric is consumed.
H Cl + H 2 O ⇔ H 3 O+ + C l−
Figure 2.1: Aqueous hydrochloric acid solution
The process of crushing the antacids to make the solution aqueous is a necessary
requirement for this practical, as adding the whole pill would not result in a quantifiable
measurement in regards to effectiveness. However, the introduction of the aqueous
solution has numerous possible impacts on the results, by crushing the capsules the
rate at which active collisions can occur is increased per unit time, hence allowing for
the titre values to be of greater validity based upon collision theory.
Due to the chemical structure and molecular mass of the active ingredients of the
antacids, the solubility and density of the compounds in water will be variable, as
displayed below in table 2.2. As distilled water has a density of 1 g /cm3 . The
compounds added that are of greater density will sediment at the bottom of the
flask/burret, while the solution of greatest solubility will dissolve best into solution and
hence be homogenised.
Brand
name
Active ingredient
Solubility
( mg/L at 25c °)
Density:
( g /cm3 )
Mylanta
C aCO3
15
2.71
Gastro
Health
M gO
12
3.58
Zantac
C 13 H 23 CIN 4 O3 S 660
0.72
Table 2.2: active compounds of antacids and solubility
Table 2.3, Variables of titration of antacid practical:
Dependent
Independent
uncontrolled
The average titer value.
The brand of Antacid, and
hence the alkaline
compounds within each of
the brands and their
neutralising impact on the
analyte hydrochloric acid.
The hegemony of the titre solutions in distilled water
the dependent variable of
alkalinity and neutralising
effect the antacid is in
regards to the independent
variable of the brand used,
it is hypothesised that the
capsulised antacid will be
the most effective.
the variation of alkaline
compound used allows for
the dependent variable to
be effected, which then
yields a result that has a
measurable impact towards
the hypothesis
The temperature/ pressure of the room
As the antacids underwent maceration, they were in a
powdered condition, as the solutions are designed to
be ingested straight into the gastrointestinal tract
many have hydrophobic functional groups and are non
homogeneous in neutral conditions, hence the rate at
which active collision in the acid base titration are
impacted and the equilibrium value is less valid,
additionally, the maccerated antacid solutions are
likely to have a varied density to that of water, and the
majority of the solution would rise to the surface of the
buret or sink to the head decreasing the accuracy and
hence the validity of the results.
Table 2.4: Controlled variables:
Controlled variable
How
Why
The dilution of the antacid
solution
By using the same volumetric
flask across dilutions, the
volume remains constant
The molarity of hydrochloric
acid used in titration
The 10mL volume was extracted
from the same solution across
each trial.
The apparatus and method
across trials
The number of trials
By following the systematic
structure consistently across
each trial
To limit the possibility of
random errors associated with
inaccurate dilution, hence
increasing the validity of the
experiment
To limit the possibility of
random errors associated with
concentration of HCl, hence
increasing the validity of the
experiment
To limit the possibility of
random errors associated with
inaccurate experimental
practices, hence increasing the
validity of the experiment
Results of titration of three known antacids:
Table 2.5: Antacid Active ingredients, Mass and Titre Values used to neutralise 10mL of 0.2mol HCl.
Titters (mL)
Brand
name
Active ingredient
Mass Antacid
(grams)
Mylanta
C aCO3
3.4
4.5
2.3
2.4
3.07
Gastro
Health
M gO
2.6
1.2
2.8
2.2
2.07
Zantac
C 13 H 23 CIN 4 O3 S 9
3.8
4.3
3.7
3.93
Trial One
Titer two(mL)
Titer
Average
Three(mL) (mL)
Calculations:
Active ingredients in antacids (all calculations will be based upon the major active ingredient, for
formulas applied, see Appendix 1.1):
A, Mylanta :
Calcium carbonate and magnesium hydroxide:
C aCO3 + 2HCl → C aCl2 + Co2 + H 2 O (major reactant)
M g(OH)2 + 2HCl → M gCl2 + 2H 2 O (assistance base)
The volume of Mylanta required to neutralize 10mL of 2mol hydrochloric acid was on average, 3.07mL:
C aCO3 + 2HCl → C aCl2 + Co2 + H 2 O
nHCl = c × v
[number of moles of hydrochloric acid in reduced volume of 10mL]
nHCl = 2 × 0.01
nHCl = 0.02moles
[0.02 moles of hydrochloric acid in 10mL solution]
Hence:
nCaCO3 = uk [nHCl ]
nCaCO3 = 21 [0.02]
nCaCO3 = 0.01moles
cCaCO3 =
n
v
cCaCO3 =
0.01
3.07×10−3
[0.01 moles of calcium carbonate in the 3.07 × 10−3 L volume]
C CaCO3 = 3.26molL−1
Therefore the experimental concentration of Mylanta was 3.26 Moles per liter.
mass
ingredients
%w/w = T otal Active
antacid mass × 100
%w/w =
mass CaCO
3
T otal M ylanta mass
m CaCo3 = nM
M = (40.078) + (12.011) + 3(15.999)
M CaCO3 = 100.1g/mol
m CaCo3 = (0.01)(100.1)
m CaCo3 = 1.001g
%w/w =
1.001
3.4
× 100
%w/w = 29.4%
Therefore the experimental percentage of active ingredients in mylanta is 29.4%.
B, GastroHealth :
Gastro: Calcium carbonate and Magnesium oxide:
C aCO3 + 2HCl → C aCl2 + Co2 + H 2 O (assistance base)
M gO + 2HCl → M gCl2 + H 2 O (major reactant)
The volume of Gastro Health solution required to neutralize 10mL of 2mol hydrochloric acid was on
average, 2.07mL:
M gO + 2HCl → M gCl2 + H 2 O
nHCl = c × v
[number of moles of hydrochloric acid in reduced volume of 10mL]
nHCl = 2 × 0.01
nHCl = 0.02moles
[0.2 moles of hydrochloric acid in 10mL solution]
Hence:
nM gO = uk [nHCl ]
nM gO = 21 [0.01]
nM gO = 0.01moles
C M gO =
n
v
C M gO =
0.01
2.07×10−3
[0.4 moles of magnesium oxide in the average 2.07 × 10−3 L volume]
C M gO = 4.83molL−1
Therefore the experimental concentration of Gastrohealth is 4.83 Moles per Liter.
mass
ingredients
%w/w = T otal Active
antacid mass × 100
%w/w =
mass M gO
T otal Gastrohealth mass
m M gO = nM
M M gO = (24.305) + (15.999)
M M gO = 40.3mol
m M gO = (0.01)(40.3)
m M gO = 0.4g
%w/wM gO =
0.4
2.6
× 100
%w/wM gO = 15.4%
Therefore the experimental weight by weight ratio is 15.4%
C, Zantac:
Zantac: Ranitidine Hydrochloride:
C 13 H 23 CIN 4 O3 S + H Cl → C 13 H 23 CIN 4 O3 S(HCl) (non-imidazole blocker of histamine receptors
(parietal glands)
nHCl = c × v
[number of moles of hydrochloric acid in reduced volume of 10mL]
nHCl = 2 × 0.01
nHCl = 0.02moles
nC 13 H 23 CIN 4 O3 =
nC 13 H 23 CIN 4 O3 =
[0.2 moles of hydrochloric acid in 10mL solution]
1
1 [nHCl ]
1
1 [0.02]
nC 13 H 23 CIN 4 O3 = 0.02moles
volume]
C C 13 H 23 CIN 4 O3 =
n
v
C C 13 H 23 CIN 4 O3 =
0.02
3.93×10−3
[0.2 moles of ranitidine hydrochloride in the average 3.93 × 10−3 L
C C 13 H 23 CIN 4 O3 = 5.089molL−1
Therefore the experimental concentration of Zantac is 5.089 Moles per litre.
mass
ingredients
%w/w = T otal Active
antacid mass × 100
%w/wC 13 H 23 CIN 4 O3 =
massC
13 H 23 CIN 4 O3
T otal Zantac mass
m C 13 H 23 CIN 4 O3 = nM
M C 13 H 23 CIN 4 O3 = C 13 H 23 CIN 4 O3
M C 13 H 23 CIN 4 O3 = 14(12.011) + 23(1.008) + (126.9) + 4(14.007) + 3(15.999)
M C 13 H 23 CIN 4 O3 = 422.26g/mol
m C 13 H 23 CIN 4 O3 = (0.02)(40.3)
m C 13 H 23 CIN 4 O3 = 8.45g
%w/wM gO =
8.45
9
× 100
%w/wM gO = 93.8%
Therefore the experimental weight by weight ratio is 93.8%
Table 2.6 Concentrations of major active ingredients in antacids investigated:
Antacid
Active ingredient
Experimental
Concentration
Mol L−1
Experimental
%W /W
%W/W
Given by
Manufacturer
Mylanta
C aCO3
3.26
29.4
35.29%
GastroHealth
M gO
4.83
15.4
29.4%
Zantac
C 13 H 23 CIN 4 O3 S
5.089
93.8
100%
(Concentration of active ingredient is not given by manufacturer, possibly due to the combination of
active ingredients or TGA guidelines6 )
Figure 2.7: concentration and weight by weight percentage for titrated Antacids
Discussion:
The experimental results indicate that Zantac has the highest active ingredient concentration
(5.089molL) and weight by weight percentage ratio(93.85%) While the Mylanta had the lowest
experimental concentration( 3.26molL ), and the zantac had the lowest weight by weight percentage
(15.4%) as shown in table 8. It can be inferred that, based on these results, Zantac is the most effective
antacid in regards to both concentration and percentage weight by weight. However, the raw tire value
illustrates that gastro health neutralised the acid with the lowest volume of antacid. Passed upon
shallow analysis, it could be stated that based on this fact gastro is the most effective antacid, however
further calculations refute this.
In regards to the hypothesis, the theory that the gastro health capsule would be the most effective was
refuted, as both its concentration and weight by weight percentage were less than that of the Zantac.
However, the results could have been impacted by the solubility of the active ingredients in water. The
high solubility of zantacs major active ingredient; ranitidine hydrochloride (660mg/L) as display in table
8 results in a homogeneous solution when added to water due to the polarity of the chlorine function
group, secondary interactions meant that the polar antacid was made homogeneous easily.
6
​(Therapeutic Goods (Listing) Notice 2003 (No. 2), 2020)
The contrasting low solubilities of the gastro health and mylanta active ingredients in combination with
their high density lead to sedimentation of the active ingredients in the buret, hence reducing the
amount of active reactions as the active ingredients were intrapped in the buret due to sedimentation,
increasing the volume required for neutralisation.
By only considering the primary active ingredients of the antacids, the impact of possible other reactive
ingredients are ignored and hence the validity and reliability of the obtained results are reduced when
comparing the obtained weight by weight percentage, it’s oberable that the results obtained were not
complementary to the claims of the manufacture, and hence the validity of the experiment is low in that
aspect. It is not possible to make a statement regarding the concentration value, as the manufacturer of
the antacids do not publicly list this information.
The invalidity of the determined values can be correlated to random, and systematic errors during the
investigation. One possible source of random error being the inconsistency of the determined endpoint
of titration, as the result is based on a visual observation, it is highly subjective, and is based on
perseverance rather than quantitative data, hence resulting in random errors across the trials. To
counteract this, three trials were conducted to form averages for each antacid, to further mitigate the
impacts of end point subjectiveness, more trials could be run.
Further the general upshift in results of weight by weight percentage could be the result of a systematic
error. A possible source of systematic error in this practical could have resulted from the indicator used
(methyl orange), in which the indication range is between a ph of 3.2-4.4, the solution was not
necessarily at a neural ph (7) when indicating, resulting in a shift in all data..one possible alteration to
the method which would of decreased systematic error would be the implementation bromothymol
blue, which has an indication range between 6-7.6.
Furthermore, to increase the validity of the experiment, the titrations could of occured in conditions
that replicate the stomach to a greater degree. The absence of heat, and enzymes (such as Pepsin)
present in the reaction result in a less clear definition of ‘effectiveness’. The standard lab temperature
during the investigation could of been raised from 25 25° C to approximately 36.5° , which is internal
body temperature, and a catalyst such as sulphuric acid could have been supplemented to replicate the
naturally occurring pepsin.
Figure 2.8: Errors of Titration of Antacids
Error
Type of
error
Effect of Error on
Data
Possible Error Mitigation
Indication ph range
Systematic
The indicator range is
3.2-4.4, which is less
than neutral, and
hence more antacid
solutions were
required for
neutralisation across
all trials.
Implement an indicator such as Bromothymol
blue, which has an indication range that is
between 6 and 7.6, resulting in an indication
occurring at pHs closer to neutral.
Inconsistency in
determination of
endpoint
Random
Randomly shifted
data due to
inconsistency and
subjectively, and
hence reducing the
accuracy and validity
of the experiment.
Ensure that a single individual is responsible for
determining the end point, increasing the
consistency and accuracy of the experiment.
Alternate reactions
Random
While the active
ingredients of the
antacids were the
majority, the capsules
also had additional
components, of which
would impact the
indication randomly
depending on the
ingredients,
decreasing the
concentration values
validity as the side
reactions are not
accounted for.
To mitigate this, the experiment could be run
using only the primary active ingredient of the
antacids, resulting in values that are of higher
validity.
Conclusion:
It was concluded based on the experimental results that zantac was the most effective antacid
(Concentration of 5.089 Mol/L and %W/W of 93.8) and mylanta was the least effective
antacid(Concentration of 3.26 Mol/L and %W/W of 29.4) . The results are somewhat reliable based upon
the manufacturing value of %W/W for zantac, the accuracy of the experimental value was 93.8%.
Appendix:
Mylanta:
M g(OH)2 + 2HCl → M gCl2 + 2H 2 O (assistance base)
Gastro Health:
C aCO3 + 2HCl → C aCl2 + Co2 + H 2 O (assistance base)
n =c×v
n(unknown) = (molar ratio) uk [n ]
%w/w =
mass Active ingredients
T otal antacid mass
× 100
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