Practical 5

"Unveiling the Alkaline Diversity: Phenolphthalein Analysis of

Water Samples Across KP Province"

Abstract
This study aims to determine the alkalinity of various water samples gathered from
various areas of Kp province including the marble industry, lucky cement, tube
well water, drinking water, and canal water. We can determine the alkalinity of
water through titration, estimating the volume expected to neutralize bicarbonate
and carbonate particles. As a result of this practical, it is clear that the water sample
from the marble industry has the most value of alkalinity followed by canal water,
drinking water, and tube well water respectively. The higher alkalinity in water
samples from the marble industry is attributed to the presence of basic minerals, for
example, calcium carbonate, which is discharged into the water during the
handling of marble. Similarly, the higher alkalinity in water samples from a canal
is attributed to regular cycles like the disintegration of minerals like limestone or
the deterioration of natural matter. The alkalinity in drinking water and tube well
water is attributed to normal land processes, for example, the disintegration of
minerals like limestone or the presence of bicarbonate particles from soil and rock
arrangements. Alkalinity in water is important because it helps to keep the pH
stable, which is crucial for marine life and prevents corrosion. However, too much
alkalinity can cause scaling in pipes and make sanitation processes less effective.
To control water alkalinity, you can use acidic substances like sulfuric or
hydrochloric acid to balance it out. You can also use methods like aeration or ion
exchange to remove excess minerals. It's important to regularly check and adjust
alkalinity levels to keep them at the right level.

1.0 Introduction
1.1 what is the Alkalinity of water?
Alkalinity in water refers to its ability to resist changes in pH when acids are
added. It's an important parameter in water chemistry, especially in natural aquatic
systems and water treatment processes. Alkalinity is primarily due to the presence
of bicarbonate (HCO3-), carbonate (CO32-), and hydroxide (OH-) ions in the water.
1.2 Sources of Alkalinity:
1.2.1 Carbon Dioxide Dissolution:
When carbon dioxide (CO2) dissolves in water, it forms carbonic acid (H2CO3),
which then dissociates to bicarbonate ions (HCO3-) and hydrogen ions (H+). This
reaction is key in providing alkalinity to most natural waters.

1.2.2 Carbonate Minerals:

Natural sources of alkalinity include the dissolution of carbonate minerals like
limestone (calcium carbonate, CaCO3) and dolomite (calcium magnesium
carbonate, CaMg (CO3)2) in rocks and sediments.

1.2.3 Weathering Processes:

The weathering of rocks containing carbonate minerals can release carbonate ions
into the water, increasing its alkalinity.

1.2.4 Anthropogenic Activities:

Human activities such as discharges from wastewater treatment plants, agricultural
runoff, and industrial processes can introduce alkaline substances into water
bodies.

1.3 Measurement of Alkalinity

Alkalinity is typically measured through titration, where a sample of water is
titrated with a strong acid (e.g., sulfuric acid or hydrochloric acid) until a pH
endpoint is reached. The amount of acid required to reach this endpoint is
proportional to the alkalinity of the water. Alkalinity is often expressed in terms of
milligrams per liter (mg/L) or parts per million (ppm) of calcium carbonate
(CaCO3) equivalents.

1.4 Types of Alkalinity:

1.4.1 Carbonate Alkalinity:
This is the alkalinity due to the presence of carbonate ions (CO32-) in the water. It's
typically found in waters with a pH above 8.3.
1.4.2 Bicarbonate Alkalinity:
Bicarbonate ions (HCO3-) are the most abundant form of alkalinity in most natural
waters. They result from the partial dissociation of carbonic acid (H2CO3) formed
by the dissolution of CO2 in water.
1.4.3 Hydroxide Alkalinity:
Hydroxide ions (OH-) contribute to alkalinity in waters with high pH values
(greater than 10). Hydroxide alkalinity is usually minor compared to bicarbonate
and carbonate alkalinity.

1.5 Recommendations for controlling Alkalinity water

controlling water alkalinity are important for maintaining water quality, preventing
scale formation, and ensuring the effectiveness of water treatment processes. Here
are some recommendations for controlling water alkalinity:

1.5.1 Regular Monitoring:

Implement a routine monitoring program to measure alkalinity levels in your
water source. Regular testing allows you to track changes in alkalinity over time
and take appropriate corrective actions when necessary.

1.5.2 Adjustment with Acid:

If alkalinity levels are too high, you can lower them by adding acids such as
sulfuric acid or hydrochloric acid. This process, known as acidification or
neutralization, helps to reduce alkalinity and stabilize pH levels. However, it's
important to carefully calculate the amount of acid needed to avoid
overacidification.

1.5.3 Aeration:
Aeration involves exposing water to air or oxygen, which can promote the release
of carbon dioxide (CO2) and help to reduce alkalinity. Aeration methods such as
cascading water over weirs or using diffused air systems can be effective in
lowering alkalinity levels.

1.5.4 Ion Exchange:

Ion exchange is a water treatment process that involves replacing alkaline ions
such as calcium (Ca2+) and magnesium (Mg2+) with other ions such as sodium
(Na+). This can help to reduce alkalinity levels, especially in hard water with high
concentrations of calcium and magnesium ions.

1.5.5 Reverse Osmosis:

Reverse osmosis (RO) is another water treatment option for controlling alkalinity.
RO membranes are capable of removing dissolved ions, including bicarbonate and
carbonate ions, from water, resulting in reduced alkalinity.

1.5.6 Selective Precipitation:

Selective precipitation involves adding specific chemicals to water to selectively
precipitate alkaline compounds, such as calcium carbonate (CaCO 3) or magnesium
hydroxide (Mg (OH) 2). This can be an effective method for reducing alkalinity in
certain water treatment applications.

2.0 Experimental section

2.1 Apparatus
Titration flask
Burette
Sucker
Beakers

2.2 Materials
H2SO4 water sample
phenolphthalein indicator

2.3 procedure
To determine the alkalinity of water sample, we take 50mL of the water sample in
a titration flask. Then prepared 0.02N of the H2SO4 by dissolving 0.1416mL of the
H2SO4 in 250 mL of distilled water and filled it in a burette. After these add two
drops of the phenolphthalein indicator to the water sample thus the color of
solution becomes pink. Then, at that point, titrate it against the H 2SO4 solution.
Note down the volume of H2SO4 utilized until the pink disappears.

To Prepare 0.02N H2SO4 solution in 250mL distilled water

We calculate the volume of H2SO4 through the following formula
V= N (H2SO4) × Eq.Wt ×Vtotal % Purity×Density×10
Where;
“N” is the normality of H2SO4
“Eq.Wt” is the equivalent weight of H2SO4
“Vtotal” is the total volume taken V(H2SO4)=
0.02N×49×250 94×1.84×10
=0.1416mL
To determine the partial/ phenolphthalein/hydroxyl ion alkalinity of water
samples
In order to determine the partial/ phenolphthalein/hydroxyl ion alkalinity of water
samples we used the following formula
Alkalinity of water sample = v(H2SO4)× N (H2SO4)×50×1000 volume of sample
taken
Where;
“N” is the normality of H2SO4
“V” is the volume of H2SO4 used
Alkalinity of water sample = 3.5m ×0.02N×50×1000 50
= 3500/ 50
=70ppm
From the above calculations it is clear that about 70ppm of the hydroxyl ions are
present in the water sample brought from marble industry.

3.0 Results & Discussion

The table (5) shows the partial Alkalinity values of different water samples
collected from different regions of the KP province. Out of these samples five
samples were collected by our group includes water sample from marble industry,
drinking water sample, water sample from ghee industry, tube well & canal. Table
(5) is given below:

Table (5): Shows partial Alkalinity values of different water samples

S.NO NAME OF SAMPLE LOCATION NATURE OF THE Partial alkalinity

SAMPLE (PPM)
01 Canal water Sheikh Maltoon Only irrigation 18ppm
town Mardan, KP
02 Kabul river Akora Khattak Only irrigation
Nowshera, KP
03 Canal water Mandani, Normal 20ppm
 Charsadda, KP irrigation
purposes
04 River swat Hialy Dagi mukaram Only irrigation
khan,Charsadda KP
05 River swat Chakdara, KP Only irrigation 72ppm
06 River Kabul Shakh no6 sarky Only irrigation
Charsadda, KP
07 Domestic water Lower Dir, KP Waste water
08 River Kabul Mohib Banda Only irrigation
Nowshera, KP
09 Marble industry Nowshera, KP Waste water 70ppm
10 Ghee industry Shama Banaspati Waste water 24ppm
Nowshera, KP
11 well water Charsadda, KP Drinking water 18ppm
12 Tube well water Takht bhai Mardan, Drinking water 18ppm
KP
13 River water Swat River, Irrigation water 72ppm
Chakdara
14 Canal water Tangi Charsadda, KP Only irrigation

15 Well water Sangao Katlang Drinking water

Mardan, KP
16 Sugar mill water Sugar mill Mardan, Waste water
KP
17 Canal water Jalala Irrigation
canal,maedan, KP
18 Well water Amangarh Drinking water
Nowshera, KP
19 Rain water Abdul Wali khan Waste water
university Mardan,
KP
20 Stream water Jamal Garhi Irrigation
Mardan, KP
21 Dam water Palai Dam, Normal 68ppm
Charsadda, KP irrigation

The data from Table (5) shows variations in alkalinity levels across different water
sources in KP Province. Marble industry water shows the highest alkalinity which
is attributed to calcium carbonate dissolution during processing, producing
increased level of bicarbonate ion concentrations, followed by ghee industry water,
where alkalinity results from free alkalis like sodium hydroxide or potassium
hydroxide used in refining processes. Canal water's alkalinity arises from dissolved
minerals like carbonates, bicarbonates, and hydroxides of calcium and magnesium,
sourced from natural geological formations or human activities like agricultural
runoff and urban drainage. Drinking water and tube well samples also shows some
alkalinity due to dissolved calcium carbonate, magnesium carbonate, and
bicarbonates of calcium and magnesium dissolution from surrounding geological
structures into the water as it passes through rocks and soil. Alkalinity plays a
crucial role in stabilizing aquatic environments by buffering against acidity.
However, excessive alkalinity can disrupt the solubility of vital nutrients and
minerals, potentially impacting aquatic life's growth and reproduction. To control
this, minimizing alkaline substance releases from industries and agriculture.
Regular monitoring and proper waste management are essential to uphold balanced
water quality and safeguard aquatic ecosystems.

4.0 Conclusion
In conclusion, the alkalinity levels in water sources across KP Province varies from
each other, where marble industry water having the highest levels of
phenolphthalein alkalinity, followed by ghee industry water, canal water, drinking
water, and tube well samples. These variations are attributed to different sources of
alkalinity, such as calcium carbonate dissolution in marble processing and the
presence of free alkalis in ghee refining. Additionally, dissolved minerals from
natural geological formations or human activities contribute to alkalinity in canal,
drinking, and tube well water. While alkalinity is essential for stabilizing aquatic
environments, excessive levels can cause risks to aquatic life by disrupting nutrient
solubility. Control measures such as reducing alkaline substance releases from
industries and agriculture are necessary to prevent harmful impacts. Regular
monitoring and effective waste management practices are crucial for maintaining
balanced water quality and safeguarding aquatic ecosystems in KP Province.