Maram Alfi, Salma Omar, & Kayla Phillips
March, 2, 2010
General Chemistry 110 lab
Yumi Matsumura
The best Antacid that can neutralize the HCl using “Titration”
Abstract
This experiment is about to decide which antacid is the best to make the HCl neutralized. There
were two antacids that were provided which are: CVS antacid tablet and a Brioschi tablet.
These two tablets were used in order to neutralize the HCl. The method used was titration.
Titration is basically using an unknown solution with a known solution (What’s the best
Antacid?). The results were that the CVS antacid is better to use based on the price. It cost $.02
per dose. Some antacids are more effective than others and that is what showed when two
antacids were used. The CVS antacid is more effective to neutralize the HCl and easy to use.
Introduction
There are many antacids in different shapes of matter. It can be solid or liquid. Antacids are
different in the how much each antacid can neutralize the HCl. This experiment is about
comparing two antacids and knowing which one is the best to neutralize the HCl. The method
that is used to know which antacid is the best is titration. Titration was used in this experiment
with the two chosen antacid to see which one is the best antacid. Titration was about putting
HCl in a tube and then, after adding the antacid to the water, the baker was put under the tube
that had the HCl. The HCl was added to the water and the antacid in the baker into doses.
Slowly adding HCl until the water with the antacid turns purple pink. The purpose of this
experiment is to decide which antacid is the best to neutralize the HCl. There are four equations
that are used to help determine the dose that should be used with the right amount of HCl.
EQ 1
Moles HClinitial = Molarity HCl X
1L
X mL of HCl use
1000 ml
EQ 2 Moles HClNaOH neutralized = M of NaOH X 1 L
X mL NaOH used X 1 mol HCl
1000 mL
EQ 3
1 mol NaOH
Moles of HClantacid neutralized = (moles of HClinitial) - (moles of HClNaOH neutralized)
EQ 4 Moles of HClantacid neutralized/gram = Moles of HClantacid neutralized/grams antacid used
EQ 5
Moles of HClCaCO3 neutralized per dose =
(550 mg CaCO3) * (1 g/1000 mg) *(1 mol/100.09 g) * (2 mol HCl/1 mol CaCO3)
= 0.0101 mol HCl
(What’s the best Antacid?).
Experimental Method
The equipments for this experiment were: bakers, tube, holder, HCl, NaHCO3, two different
types of antacid, pipette pumps, heater, and phenolphthalein. First, the tube was full of
NaHCO3. Meanwhile, the baker was full of water till 75 mc in the baker and the antacid was
broken to the amount required based on the calculations. The first antacid was the CVS antacid
tablet. After the water has been added to the baker, and two drops of phenolphthalein were
added too using volumetric pipettes, the antacid was added based on the requirement quantity
which was 6%. After that, the antacid was heated till it boils for 2 minutes. The antacid has
been stirred. The NaHCO3 has been added to the antacid after stirring it and the NaHCO3 was
added every 30 seconds till the color turned purple pink. These steps were used to the other
antacid, Brioschi tablet, following the same steps.
Results
The antacids that were used based on required quantities. The following table shows the types
of the antacids that were used and the specific amount of each.
The antacids

Brand names



Tablet or liquid
Tablet to be crushed (Y/N)
Acid/Antacid mixture to be
boiled

An amount of antacid to be
used


Active Ingredient(s)
grams/dose
Antacid cost per container
Antacid 1
Antacid 2
CVS antacid
Brioschi
Tablet
Tablet
Y
Y
Antacid
Antacid
6%
.14%
CaCo3
NaHCO3
3.29
8.49


Size of container (#tablets
or mL)
150 Tablets
240g
$ .02
$ .06 per dose
Cost per dose
Following the equations that are mentioned above, these equations were used to choose the
right amount of each antacid that has been used.
For the CVS antacid
Equation 5
Moles of HClCaCO3 neutralized per dose =
(500 mg CaCO3) * (1 g/1000 mg) *(1 mol/100.09 g) * (2 mol HCl/1 mol CaCO3)
= 0.099 mol HCl
.006/.099 =.06 the percentage of how much was used from the CVS antacid
When the NaHCO3 was added to the antacid after boiling, the amount of how much NaCOH3
was measured to know how much was used to make the antacid purple pink.
For the CVS antacid, the NaHCO3 started with 7 ml and ended at 50 ml = 43 ml.
Discussion
The purpose of this experiment is to know what the best antacid is to neutralize the HCl. As
mentioned, two antacids were used in this experiment. Both of these antacids were used with a
specific amount based on the calculations and the equations. Following the steps and after
heating the antacids, it has been noticed that the two antacids were similar in how much it took
to boil and also to turn to a purple pink color. At the start of doing the experiment, the
calculations were needed to decide how much should be used of each of the antacid, such as
the calculation of the CVS antacid,
Moles of HClCaCO3 neutralized per dose =
(500 mg CaCO3) * (1 g/1000 mg) *(1 mol/100.09 g) * (2 mol HCl/1 mol CaCO3)
= 0.099 mol HCl
The calculations were helpful because it was needed to know how much to use and not choose
random amounts which may lead to different results. Moreover, when the NaHCO3 was added
to the two antacids, the both antacids took almost the same amount of NaHCO3 and time to
change to a purple pink color. That was clear when the calculations were done. The CVS antacid
started at 7 ml and ended at 50 ml which equals 43 ml. The Brioschi antacid started at 5 ml and
ended at 48 ml which equals 43 ml. If there was a mistaken amount in any of these elements,
the results will be different. There can be errors when adding more than two drops of
phenolphthalein or use more than the amount required of the antacid. Moreover, the errors
can be in how to add the liquids in the baker using the pipette pump. Using the pipette pumps
should be in a carful way because not being careful may cause the damage for the baker and
the pipette pumps. The best way to prevent errors is to ask for help for the teacher assistant or
the professor and follow the steps carefully and understand them.
Reference
Blackboard document
What’s the best Antacid?. ( 2010). Chemistry lab.