alkalnity of water with respect to food

1. University Of
Manitoba
Alkalinity
Lab :- 02
Course code:- FOOD4260
Group: - 1
Submitted By
Name: - Gursewak Singh
UM ID: - 7876293
Department of FoodScience and Statistic
Submitted To
Name: - Dr. Chamila Nimalaratne
Lecturer of FOOD4260
Department of FoodScience
Submission Date:- 28 February 2022

2. Introduction: -Alkalinity is a boundary that is estimated on practically
all ecological examples - drinking water, normal waters, dirtied waters,
sewage, and modern squanders. Alkalinity alludes to the buffering limit
of water tests and to their capacity to kill acidic contamination from
precipitation or wastewater. For city sewage or modern squanders, how
much alkalinity is significant in deciding the kind of treatment which
ought to be utilized. (Water Science School , 2018)
Alkalinity is essentially brought about by the presence of carbonate (C03
2-) and bicarbonate (HC03-) particles, despite the fact that hydroxide
(OH-) particles may likewise contribute, particularly when there is
modern contamination. (Nimalaratne, 2022). Living organic entities, for
example, amphibian life, work best in a pH scope of 5.0 to 9.0 and levels
of 20 to 200 mg/L are average alkalinity values for new water.
(Environmental Geochemistry, 2008). Whenever the pH is above 8.3,
carbonate (CO3 2-) is the essential supporter of alkalinity; when the pH
is beneath 8.3, bicarbonate (HCO3-) turns into the ruling component.

3. (Environmental Geochemistry, 2008). The upsides of alkalinity are
accounted for in units of "mg CaCO3/L". (Nimalaratne, 2022).
Now, if we talk about titration process that is the process that is very
common to understand and know the presence of ion in our sample. We
use four different such as tap water, bottled water and two unknown
samples and two different end point by using the two different indicators
such as phenolphthalein which will show the presence of hydroxide and
carbonate ion, bicarbonate and bromocresol which helps to show the
presence of bicarbonate ion in your sample and give us the total
alkalinity of our sample.
The primary goal of this lab was to identify the phenolphthalein
alkalinity and total alkalinity of the given samples and also, give a
chance the understand the most common and old technique of titration.

4. Methods and Material: - (Nimalaratne,2022)
All the material and methods of doing experiment is mentioned in the lab manual.
We can follow it by step by step to get best result.
In sample, we are using tap water, bottled water and two unknown sample that are
given by the lab coordinator. In the similar way for equipment, we are using
Burette with burette stand, Erlenmeyer flask 100 or 250 ml, Beakers, Small short
stem funnel, Graduated cylinders.
In chemical, standard hydrochloric acid 0.02 N, Phenolphthalein indicator,
Bromocresolgreen indicator, Distilled water and unknown sample.
We follow whole process of acid content of food that mentioned in the lab manual.
So, there is not valid modification that we applied in the process.

5. Results : -
Table 1 : - It is showing the raw data results that we collectedfromdifferent
samples from the experiment. (Nimalaratne,2022)
Sample Name
/Number
Sample Size Initial reading First
indicator (
end point)
Second
indicator
( END
POINT)
Tap water 100ml
100ml
0
0
0
0
9ml
10.5 ml
Bottledwater 100 ml
100ml
0
0
0
0
6 ml
7.5 ml
Unknown 1 10 ml
10ml
0
0
22.5 ml
23.4 ml
23.5 ml
24.9 ml
Unknown 3 10ml
10ml
0
0
10.5ml
8.9ml
21 ml
19.4 ml

6. Table 2: - The table is showing the result of HCl Used in Phenolphthalein
alkalinity and HCl usedin total alkalinity of tap water and phenolphthalein
alkalinity and total alkalinity inmg CaCO3/L for tap water sample.
Sample Sample
size
Amount usedof
HCL for
Phenolphthalein
alkalinity
Amount
usedof
HCL for
total
alkalinity
Phenolphthalein
Alkalinity ( mg
caco3/L
Total
alkalinity
( mg
Caco3/ L
Tap
water 1
100 ml 0 9ml 0 90
Tap
water
sample
2
100ml 0 10.5 ml 0 105

7. Table 3: - The table is showing the result of HCl Used in Phenolphthalein
alkalinity and HCl usedin total alkalinity of tap water and phenolphthalein
alkalinity and total alkalinity inmg CaCO3/L for bottledwater sample.
Sample Sample
size
Amount usedof
HCL for
Phenolphthalein
alkalinity
Amount
usedof
HCL for
total
alkalinity
Phenolphthalein
Alkalinity (mg
caco3/L
Total
alkalinity
(mg Caco3/
L
Bottled
water 1
100 ml 0 6 ml 0 60
Bottled
water
sample
2
100 ml 0 7.5 ml 0 75

8. Table 4: - The table is showing the result of HCl Used in Phenolphthalein
alkalinity and HCl usedin total alkalinity of tap water and phenolphthalein
alkalinity and total alkalinity inmg CaCO3/L for unknown sample 1.
Sample Sample
size
Amount usedof
HCL for
Phenolphthalein
alkalinity
Amount
usedof
HCL for
total
alkalinity
Phenolphthalein
Alkalinity ( mg
caco3/L
Total
alkalinity
( mg
Caco3/ L
Unknown
1 sample
1
10 ml 22.5 ml 23.5 ml 2250 2350
Unknown
1 sample
2
10ml 23.4 24.9 2340 2490

9. Table 5: - The table is showing the result of HCl Used in Phenolphthalein
alkalinity and HCl usedin total alkalinity of tap water and phenolphthalein
alkalinity and total alkalinity inmg CaCO3/L for unknown sample 3.
Sample Sample
size
Amount usedof
HCL for
Phenolphthalein
alkalinity
Amount
usedof
HCL for
total
alkalinity
Phenolphthalein
Alkalinity ( mg
caco3/L
Total
alkalinity
( mg
Caco3/ L
Unknown
3 sample
1
10ml 10.5ml 21 ml 1050 2100
Unknown
3 sample
2
10 ml 8.9 ml 19.4 ml 890 1940

10. Sample calculation: -
Phenolphthalein Alkalinity For unknown 3 :
mg CaCO3/L = (V1 x N x 50 000)/ ml
So we are know the V1 = 10.5 ml that is used in phenolphthalein alkalinity
And Sample = 10 ml
So, mg CaCo3/L = ( 10.5 * 0.02 N* 50000)/10 ml
Mg CaCo3/L = 1050 mg CaCo3/L
TotalAlkalinity For unknown3 : -
mg CaCO3/L = (V2 x N x 50 000)/ ml
So we are know the V2 = 21 ml that is used in phenolphthalein alkalinity
And Sample = 10 ml
So, mg CaCo3/L = (21ml * 0.02 N* 50000)/10 ml
Mg CaCo3/L = 2100 mg CaCo3/L

11. Discussion:-
Our most of water sample shown in the table 2 and table 3 which are normal tap
water and bottled water. They do not have phenolphthalein alkalinity means they
do not contain the carbonate ion and hydroxide in the sample. So, this is the major
reason we did not notice any colour change at first step but if we talk about total
alkalinity then we noticed the change to blue, which means we have bicarbonate
ion present in both samples. After titration process,we got light yellow color
which means we remove all alkalinity ion from the sample or maintain the pH of
our water sample. There is theory behind why we did not notice any color change
from water sample that is the sample is remains colorless throughout the range of
acidic pH levels but begins to turn pink at a pH level of 8.2 and continues to a
bright magenta at pH 10 and above. (Kozlowski, 2020). If hydrogen ions (H+, as
found in an acid) were added to the pink solution, the equilibrium would switch,
and the solution would be colorless. Adding hydroxide ions (OH-, as found in
bases)will change the phenolphthalein into its ion and turn the solution pink.
(Kozlowski, 2020). This is the same what happened with us that our sample
already contain the hydroxide ion when we added indicator it reacts and did not
show any colour change. If we talk about our unknown sample (table 4 and table 5)
then we all got phenolphthalein color and bromocresolcolor, which means we got

12. all three ion which carbonates ion, hydroxide ion and bicarbonate ion in our
unknown sample.
Secondly, now if we talked about phenolphthalein alkalinity and total alkalinity,
then in table 2 and table 3 we did not get any color change which means our
phenolphthalein alkalinity is shown zero and, but we got some amount of total
alkalinity because of presence of bicarbonate ion or bromocresolcolor change.
If we talk about unknown sample 1 and 3 (table 4 and table 5) then we got high
amount of phenolphthalein alkalinity and total alkalinity. Which is higher as
compared to water sample alkalinity. Which means our unknown have higher pH
as compared to water sample and take more amount HCl in the titration. Regardless
of the starting pH, the higher the alkalinity of the water source, the more acid is
required to reduce pH to 5.0. (Buechel, 2021).
As we perform our experiment in lab, the initial step of the titration is the addition
of few drops of the phenolphthalein indicator and started performing the titration
process until you notice the colour change from light pink to clear ( transparent)
and then for the total alkalinity, add some drops ofbromocresolindicator in the
same sample and continue doing the titration process until you notice the colour
change from green to light yellow or pale yellow.
There might be some error in the experiment that we have number of solutions
which can create problem or confusion to identify which one is which solution.

13. Also, sometimes we did not properly know which is the end point of the process.
So, we add extra amount of HCL, and which change our final results.
Conclusion:-
In conclusion, we can say that the titration process is properly done and successful
and learned about how total alkalinity and phenolphthalein alkalinity of water
sample and given unknown samples. Firstly, bicarbonate ion, hydroxides and
carbonate ions is very important in to understand our alkalinity. We measure our
all objectives in our process, so we lead to our final product. Moreover, everybody
should know their process well to get the correct final product.
Reference :-
Works Cited
(n.d.).
Nimalaratne, C laboratory manual winter term 2022, water mangemnt in food
process.food4260.
Buechel, T. (2021, 11 09). water aklanity vs pH in your growing pedium-whatis
the relationship between Acid used and alkalinity . Retrieved from
PROMIX: https://www.pthorticulture.com/en/training-center/water-
alkalinity-vs-ph/
Environmental Geochemistry. (2008, 10 17). Sciecne direct . Retrieved from
Alkalnity an overview / ScienceDirects overviews :

14. https://www.sciencedirect.com/topics/earth-and-planetary-
sciences/alkalinity
Kozlowski, R. (2020, 02 16). sciencing . Retrieved from why does phenolphthalein
colour change : https://sciencing.com/phenolphthalein-change-color-
5271431.html
Water Science School. (2018, 08 August ). UGSG science for changingworld .
Retrieved from alkalnity and water/ US geological survey :
https://www.usgs.gov/special-topics/water-science-school/science/alkalinity-
and-water