ENVIRONMENTAL CHEMISRTY ASSINGMENT
Roll# CH-0119-115
Full Name: TARIQ ALI S/o MUHAMMAD ASHRAF MEMON
Department: Chemistry
Class: BS-II
Semester: Third (3 rd )
Subject: Environmental Chemistry
Teacher: Prof.Naseem-ul-Ghani Qureshi
Batch: 2k19
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SHAH ABDUL LATIF UNIVERSITY KHAIRPUR
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1. What is mean by Eutrophication of nitrate and phosphate?
Answer: The term eutrophication is defined as increased or excess amount of nutrients in water
such as minerals, nitrates, sulphates, phosphates etc.
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The process in which water receives higher concentration of nutrients i.e. nitrates, sulphates and
phosphates than their required limit. Therefore eutrophication of nitrate and phosphate means
excess amount of phosphate and nitrates in water.
 Causes/Sources of Eutrophication of Nitrates and Phosphate
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Nitrogen and phosphorous are essential elements for growth of plants and also for animals.
These substances used in fertilizers. When fertilizers are used in excess they cause the
reason for deposition of nitrates and phosphate.
Detergents also contain nitrogen and phosphate when these are drained into rivers, lakes
they also causes eutrophication of nitrate and phosphate.
Poor sewage treatment also causes of eutrophication of nitrate and phosphate.
Dead plant and animals are the source of nitrogen fixation, this process increase the
amount of nitrates in soil. Converging of dead organisms into nitrates as given as under;
Dead Organism
Decomposers (Fungi and
bacteria) converts it into
Ammonium by process of
Ammunificatin
Ammonium(NH4+)
Nitrites (NO2-)
Nitrification
Nitrates (NO3-)
Nitrification
 Major effects of Eutrophication of nitrate and phosphate
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Eutrophication also known as algal bloom; due to accumulation of nitrates and phosphates
alga produce in water.
Production of algae in large number causes reduction of photosynthesis because sun light
can’t easily reach on plants due this aquatic living organisms’ food chain disturbed.
It’s not only effect on plants but also other organisms life.
 Control on Eutrophication of nitrate and phosphate
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SHAH ABDUL LATIF UNIVERSITY KHAIRPUR
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It can be reduced by minimizing pollution sources
Less use of fertilizers containing nitrogen and phosphate.
By using organisms that reduce the production of algae.
Except these there are many other sources through which we control eutrophication
of nitrate and phosphate.
2. What are toxic metals found in the water? What are the hazards one can expect from
drinking contaminated water which contains heavy and toxic metals?
Answer:
 Toxic Metals Founds in Water
Water is the essential substance for all living organism. It is used for many purposes i.e. drinking,
washing, fertilizing, manufacturing and so on. Due to anthropogenic and global activities, it has been
continuously become harmful by toxic metals and other wastes.
o Following are the major toxic metals found in water;
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Zinc (Zn)
Lead (Pb)
Chromium (Cr)
Mercury (Hg)
Copper (Cu)
Nickel (Ni)
Cobalt (Co)
Arsenic (As)
Cadmium (Cd)
 Health Hazards due to drinking contaminated water contains heavy toxic metals
Drinking contaminated water contains heavy metals causes following known diseases;
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Diseases caused by Cadmium
Itai-Itai disease, liver/kidney lesions, osteoporosis, hypertension
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Diseases caused by Lead
Calcium deficiency due to accumulation of lead in bones, coma, convulions, and many other diseases
by disturbing neurological & musculoskeletal systems
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Diseases caused by Chromium
Nose ulcer, Asthma, Hemolysis, and damage to DNA, liver, carcinoma and kidney
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Disease caused by Arsenic
Anemia, hypertension, dementia, Alzheimer’s, bladder cancer and so on
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Diseases caused by Mercury
Damage to central systema nervosum, visual disorders, nose and skin irritation, renal toxicity etc.
 Diseases caused by Cobalt
Seizures, growth retardation, asthma, interstitial lung diseases, increase red blood cells, thyroid deficiency,
emphysema, and paralysis of systema nervosum.
 Diseases caused by Zinc
Chest tightness, headache, nausea, gastrointestinal problems, and immune toxicity
 Diseases caused by Copper
Liver and Kidney infections, Wilson’s, anemia, damage animal tissues, melena, jaundice etc.
3. Sulphur is also one of the environmental pollutants found in land, rocks and water? What do
you mean by rotten egg smell?
Answer:
 Sulphur is also one of the Environmental Pollutants Found in land, rocks and water
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Introduction to sulphur:
Sulphur is the second member of VIA group of periodic table. Group VIA also known as Oxygen
Family or Chalcogen. It has symbol “S”. Its atomic number is 16 while atomic mass is 32 a.m.u.
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Occurrence
Sulfur is fifth most common on earth and tenth most common by mass in the universe. Sulphur on
earth usually occurs as sulfide and sulfate minerals. In air it usually occurs as combined state as
Sulfur oxides etc. It is also found near hot springs and volcanic.
 Sulfur as Environmental Pollutant
Sulfur itself is not cause of pollutant for environment but its compounds i.e. SO2, H2S, H2SO4 and
other oxides, mineral ores and sulphur metalized become the causes of environmental pollution.
Some of these causes are defied as under.
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Photochemical Smog (cause of air pollution)
Photochemical smog is a complete pollutant mixture of partially oxidized hydrocarbon, ozone &
other oxidant. A type of photochemical smog called as London or classical smog associate with
use of traditional fuel and coal. These fuel and coal produces unburned carbon soot and elevated
levels of atmospheric sulphur dioxide. Due to presence of a mild reducing agent and present of
week acid, overall properties are reducing and acidic where the atmosphere is humid. This causes
eye and other membrane irritation and also adversely affects plant growth and other serious ecotoxicological problems.
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Acid Rain (causes of air, water, rocks and soil pollution)
Acid rain is the deposition an earth of dilute solutions acids (specially sulphuric and nitric
oxide) with rain fall. Two predominant acids in acid rain are sulphuric and nitric acid. SO2
mainly comes from burning coal and oil power generating industries, industrial bowlers and
smelters. During the day time and conditions of low humidity in the pressure of
hydrocarbons and nitrogen oxides, the predominant reaction is oxidation of sulphur to
sulphuric acid, sooth particles are strongly involved in catalyzing the oxidation of sulphur di
oxide.
o Formation of Sulphuric acid
SO2 + hv → SO.2
SO2 + O2 → SO.4
SO.4 + O2 → SO3 + O3
SO3 + H2O → H2SO4
Acid rain is very destructive to lakes and rivers, killing fishes and destroying phosphate
resources on which aquatic plants depend for nutrition. Soil is likewise affected as
acidification due to acid deposition and certain biological processes with the soil erodes
fertility, it also affect the originality statue.
 Rotten Egg Smell
Rotten egg smell is commonly used for Hydrogen Sulphide gas H2S.Because it has an
offensive rotten egg odor. It is highly flammable and respiratory inhibitor. It is created
naturally by decaying organic matter and is released from sulphur hot springs, liquid
manure, sewage sludge and other wastages.
It may be harmful for health when inhaled in high concentration. It causes burning of skin
and eyes, sensation, iratest and watering of eyes, coughing and aging nausea/vomiting,
unconsciousness, coma or may be lethal to death.
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