1 : 2
0.0136: 0.0272 (double) moles of hydrochloric acid needed to react.
Moles x concentration = volume of HCL needed
1000
0.0272=0.0544 x 1000 =54.4Cm3
- The chosen concentration of HCL.
54.4cm3 of HCL is the amount that can be neutralised by the 680mg of CaCO3
MgCO3 =80mg 0.08g
Moles = 0.08 =0.00095 moles (x 2 tablets)
84 =0.0019 moles
MgCO3 + 2HCL MgCL2 + CO2 + H2O
1 : 2
- :0. 0038 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCLE needed
1000
0.0038 = 0.0076 X 1000 = 7.6cm3
7.6cm3 is the amount of HCL that will be neutralised by 80mg of MgCO3
54.4cm3 + 7.6cm3 =62cm3 of HCL that can be neutralised by this tablet.
Bisodol
CaCO3 = 522mg 0.522g
Moles = 0.522 = 0.00522 moles (X 2 tablets)
100 =0.01044 moles
CaCO3 + 2HCL CaCL2 + C02 + H20
1 : 2
0.01044:0.02088 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.02088 = 0.04176 X 1000 = 41.76cm3
41.76cm3 is the amount of HCL that can be neutralised by 522mg of CaCO3
MgCO3 =68mg 0.068g
Moles = 0.068 = 0.000809 moles (X 2 tablets)
-
=0.00161 moles
MgCO3 + 2HCL MgCL2 + CO2 +H2O
1 : 2
0.00161:0.00322 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.00322 = 0.00644 X 1000 = 6.44cm3
0.5
6.44 cm3 is the amount of HCL needed to neutralise 68mg of MgC03
NaHC03 = 64mg 0.064g
Moles = 0.064 = 0.000761 moles (X 2 tablets)
84 =0.00152 moles
NaHCO3 + 2HCL NaHCL2 + CO2 + H2O
1 : 2
0.00152: 0.00304 (double) moles of hydrochloric acid that can react.
Moles X concentration = volume of HCL needed
1000
0.00304 = 0.00608 X 1000 = 6.08CM3
5.12cm3 is amount of HCL that will be neutralised by64mg of NaHCO3
41.76cm3 + 6.44cm3 + 6.08cm3 = 54.28cm3
Settlers
CaCO3 = 500mg 0.5g
Moles = 0.5 = 0.005 moles (X2 tablets)
- =0.01 moles
CaCO3 + 2HCL CaCL2 + CO2 +H2O
1 : 2
- 0.02 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.02 = 0.04 X 1000 = 40cm3
0.5
40cm3 is the amount of HCL that will be neutralised by 500mg of MgCO3
Boots
CaCO3 = 200mg 0.2g
Moles = 0.2 = 0.0002 moles (X 2 tablets)
-
=0.0004 moles
CaCO3 + 2HCL CaCL2 + CO2 + H2O
1 : 2
0.0004: 0.0008 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.0008 = 0.0016 X 1000 = 1.6cm3
0.5
1.6cm3 is the amount of HCL that will be neutralised by 68mg of CaCO3.
NaCO3 = 60mg 0.06g
Moles = 0.06 = 0.000722 moles (X 2 tablets)
-
= -.00144 moles
NaCO3 + 2HCL CaCL2 + CO2 + H2O
1 : 2
0.00144: 0.00288 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed.
1000
0.00288 = 0.00576 X 1000 = 5.76cm3
0.5
5.76cm3 is the amount of HCL that will be neutralised by 68mg of CaCO3
NHCO3 =60mg 0.06g
Moles = 0.06 = 0.0008 moles (X 2 tablets)
-
= 0.0016 moles
NHCO3 + 2HCL CaCL2 +CO2 + H2O
1 : 2
0.0016: 0.0032 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.0032 = 0.0064 X 1000 = 6.4cm3
0.5
6.4 cm3 is the amount of HCL that will be neutralise by 68mg of CaCO3
1.6cm3 + 5.76 + 6.4cm3 = 13.76 cm3
Boots fruits
CaCO3 =500mg 0.5g
Moles = 0.5 = moles (X 2 tablets)
-
= 0.01 moles
CaCO3 + 2HCL CaCL2 + CO2 + H2O
1 : 2
0.01 : 0.02 (double) moles of hydrochloric acid needed to react.
Moles X concentration = volume of HCL needed
1000
0.02 = 0.04 X 1000 = 40cm3
0.5
40cm3 is the amount of HCL that will be neutralised by 68mg of CaCO3.
Method
When proceeding with this experiment we would place two tablet of each type into a mortar and use a pestle to paste it into a powder. But before this every tablet was weighed electronically to 2dp allowing a certain degree of accuracy and calculation of the amount of hydrochloric acid. This was done to speed up the reaction by increasing the surface area of which the compound could work on the hydrochloric acid so we could fit more into the lesson. Then the powder was added into a beaker with distilled water and universal indicator to check the p. H and any changes that might occur in it. Finally hydrochloric acid was added into the solution till a change in colour was visible. The colours that were likely to be seen would be a pink/ purple colour indicating a strong alkaline presence due to the tablets. If the solution turned green as it did it was stirred to a purple colour before any more hydrochloric acid was added this was an added variable and greatly increased the accuracy of the results. This would be repeated twice to avoid any anomalies and after every experiment the equipment used was washed thoroughly to avoid any contamination of results.
Fair test
To maintain a fair test situation in this experiment I shall set a few parameters that must be met to ensure the greatest and fairest accuracy in my results.
Any leftover hydrochloric acid shall be disposed of properly and not put back into its original container to prevent contamination and loss in accuracy of future results in any experiment.
Then same set of tools should be used every time but after each experiment everything should be properly washed to also not contaminate the other experiment.
To make sure as much antacid as possible is poured into the beaker to which hydrochloric acid should be added. And no antacid powder is lost or pushed out of the morter when being pasted.
Every single liquid is measured before being used to prevent inaccuracy through anomalous results. And also the beaker used and the measuring cylinder is washed to prevent contamination and anomalies.
To reset the electronic scale every time so no over and under weighing of any antacid is made rendering the exam inaccurate.
Safety precautions
For safety precautions a lab coat shall be worn and if there is none available the blazer should be taken off, sleeves rolled up, and tie tucked in. also goggles should be worn at all times. No experiment shall be left unattended at any time and only two or three people should be working on any experiment at any one time to reduce any accident caused by over crowding.
Results
Amount of hydrochloric acid neutralised cm3.
Analysis
The results gained were on the whole what I would call very accurate except the first bisodol which an anomaly, which could have been due to carelessness or some type of contamination. And my prediction, which listed rennie as the greatest neutraliser due to my preliminary result, was right as it neutralised the most. Also other factors that could have made the first bisodol reaction out of sync with the rest could be too much hydrochloric acid measured out or even a gram or two more antacid was powdered causing an increase in the amount of hydrochloric acid neutralised. Another factor that could have made my results anomalous could be the fact of other groups which could have returned some hydrochloric acid back to the original container contaminating it, this could have been possible as the groups all doing the same experiment of ten swapped bottles, this factor I didn’t take into account and could have been a variable in my fair test list.
Conclusion
This experiment went quite well but as it was my first time doing this type of experiment I do not know if it went as the way that it should as in result wise, speed and overall evaluation of procedure. If I were to try this experiment again to improve it I would only use one personal source of hydrochloric acid and tablets so as to avoid any contamination which may explain my off key bisodol result. I would use titration in which to add my hydrochloric acid because this time I did not use titration but just measured some liquid out and poured it in but with titration it may be used for more than one experiment, make it quicker and a lot accurate. Finally if I were to do it again I would measure the amount of gas given off and also time the experiment to find out which is the quickest tablet to neutralise a certain amount of hydrochloric acid in a certain amount of time and with this I would be able to go on and prove which is the fastest acting tablet and why could it be because of actual make up of the tablet? (Mg or Ca) or just the concentration of the tablet itself.
I have also found that for over all price boots home brand is the cheapest. But with rennie relief being the most expensive per tablet as there were fewer tablets per packet. This is not surprising as in the neutralisation table rennie neutralised the most hydrochloric acid then bisodol, settlers and lastly the two boots brands. The results can be said to be in correlation with the price as the more you pay the higher quality the antacid you receive.
Even though it was the cheapest and was the second top neutraliser bisodol was not the most cost affective as it contains only 28 tablets this can be said for rennie relief as it was the top neutraliser by far but had only 24 tablets but boots the bottom neutraliser has 80 tablet per packet, is the most expensive but the cost per two is the lowest by far and there fore can be said to be cost affective.
