What Are Some Questions Environmental Chemists Try to Answer?
Mega listing of top twenty-five interview questions on environment which will aid y'all to succeed in an interview.
Q.one. What is environs ?
Ans. If we exercise non want to become into the intricacies of the term, then we can define environs as everything that surrounds us. Whatsoever we encounter effectually us is confined to the living component of the human being eco-system. With time, the concept has undergone modifications. Today, environment means a unmarried organisation of the interacting living and non-living natural components of the earth.
But the earth is not the just planet of the solar family, which again belongs to our home Galaxy — the Milky way. There are almost 100 billion such galaxies floating in the vast universe, each containing about 100 billion stars!! In this universe, not a single event can be said to be isolated, and no object is independent of the residue.
Since everything is interrelated with every other thing, logic demands-that the entire universe is our environment. Simply, for practical reasons, environmental report deals only with the arrangement of interaction between non-living and living components of the earth.
In 1977, the first international briefing on Ecology Education was held in Tiflis (capital letter city of Georgia Democracy). The plan was organised by UNESCO and UNEP, and hither it was noted that "the environment includes a circuitous of natural, built and social components in the life of humanity".
Q.two. Describe the principal characteristics of environment.
Ans. The principal characteristics of the surroundings accept been listed below:
(i) At any given point of time, the environment of any area is the sum full of all biotic elements and the abiotic elements around them.
(ii) The three basic components that institute the structure of the surroundings are biome, habitat and energy,
(iii) The elements of the environment are systematically organised and interact with 1 another to maintain the integrity of the organization.
Thus, the environment is a perfectly functioning system:
(iv) The input of solar energy is responsible for the functioning of the system.
(v) The environment is an open up system since in that location is a continuous inflow and outflow of affair and energy.
(vi) The productivity of the surround is determined by the availability and amount of energy.
Q.3. Requite a cursory business relationship of the components of environment.
Ans. The three basic components of environment are:
(I) Abiotic (concrete or inorganic) components,
(2) Biotic (organic) components, and the
(III) Energy components.
Again, the abiotic components of the environment consist of:
(a) The lithosphere — the chief reservoir of mineral nutrients,
(b) The atmosphere — the chief reservoir of gases essential for organic life, and
(c) The hydrosphere — the master reservoir of liquid water.
The biotic component of environment includes all kinds of organic life, ranging from microorganisms to plants and animals, including man.
Free energy is the third component of surround, which is indispensable for the generation and sustenance of all forms of organic life. The sun is the master source of energy in the environment. Geo-thermal energy is yet another type of energy. Since photosynthesis is essential for the beingness of organic life, nosotros find that life is confined to merely those regions where solar energy tin can be captured for photosynthesis.
This forms a narrow belt of life that extends from most 180-210 one thousand below sea level to almost half-dozen km (snow-line in mountain ranges). This is known as the Biosphere, which tin be said to be a sparse film (1/1000th) when we consider the globe'southward radius (6,370 kms).
Q.4. Explain with examples the natural changes of surroundings.
Ans. Almost everybody is fascinated by the notion of change. Right from the day they are born, till the moment they exhale their final, human being beings experience a diversity of change. They are all familiar with the sunshine and sunset and passage of day into night, as well as the change of the seasons.
Nosotros all notice that the weather in one year is never quite similar to the weather in previous years. Allow us take for example the Monsoon Rains in West Bengal. A few years ago, the rains arrived in Bengal by early on June and Oct was sunny and pleasant. Now, the rains arrive much later, and the festivities of October are marred by the showers.
Environmental change is studied past scientists from environmental, geographical and geological disciplines. The work of those scientists have delved into the intricacies of the past environments and finally confirms that environmental change is real, diverse and complex.
Q.5. Ascertain environmental s tudies.
Ans. There are several fields of study associated with the environment. With time, man realized the growing importance of maintaining his surround, and subjects such equally ecology, environmental applied science, ecology sciences, environmental studies etc. gained popularity.
There is a fundamental difference between environmental science and environmental studies. The onetime lays emphasis on scientific qualities and problems of environmental interest, while environmental studies focus on questions related to ecology ethics and aesthetics.
The concern for preserving the surround is a relatively new phenomenon. In that location was a fourth dimension when man would derive the maximum benefit from his surroundings, without thinking of the consequences. Information technology was but since the 1950s that nations of the world started conservation and wise utilization of their natural resources — such as h2o, soil, fuel, flora and fauna.
It has been accepted that nature is a treasure-house that provides us with food, water, energy, medicine and diverse other amenities. No wonder the prevention and protection of the surroundings has become and then crucial.
Developed countries accept fabricated considerable progress in the field of protection and conservation of the environs on a-long-term basis. However, the developing nations, were quite belatedly in understanding the gravity of the situation, and, hence, they are lagging behind.
Q.6. Explicate the necessity of environmental studies.
Ans. The natural resources of the earth — which include air, water, soil, flora and brute represent our environment. For the benefit of the present and hereafter generations, these priceless resource should exist safeguarded, by means of careful planning and management.
At the end of the 20th century, we are realising the acute environmental crisis every bit an impact of indiscriminate and ignorant utilisation of natural resources. The ascension in population and need for infinite and basic amenities has led to overutilization of the available resources.
In society to create an sensation among the masses almost the importance of proper utilization and conservation of the resources, environmental education has become a must.
Q.7. What is the m eaning and objective of environmental education ?
Ans. Ecology education is the process in order to create awareness and sensitivity to the full environment by developing appropriate attitudes and acquiring adequate cognition and skills with the purpose of solving environmental bug.
The following may be suggested every bit the objectives of any environmental education programme:
A) To develop proper attitudes and skills for agreement and appreciating the interdependence of man and his environment,
b) To use natural resources carefully and adequately,
c) To formulate a new behavioural code with the aim of improving the overall quality of life for the future generations.
Q.8. What do y'all hateful by environmental c hange ?
Ans. Ecology factors are, naturally, variable. For example, air temperature varies on a diurnal and almanac basis. In order to measure out sustained temperature changes, nosotros take average values for days, months, seasons, years, and even longer periods.
And then, the similar averages are compared when it is found that the mean temperature for one year is greater than that in the previous year; we know that a change has occurred.
It must be kept in listen that average values should not be treated equally some sort of norm. Boilerplate values for all the principle atmospheric variables over a menstruation of thirty years are used to defined "climatic norms". This term is oft misleading, since it tries to establish that the climatic norms are somehow permanent.
However, current thinking suggests that the climate is e'er changing. The climatic norms of one generation may exist some other generation's climatic extremes. Thus, we may conclude from this argument that — alter is the norm, constancy the exception.
In this context, scientists have found that environmental variables display three basic types of changes:
(i) A discontinuity, which is an precipitous and permanent change in the average value,
(two) A trend, which is a polish increase or decrease (not necessarily linear in nature) in the average, and
(iii) A function, which is a regular or irregular change characterized by at to the lowest degree two maxima (or minima) and one minimum (or maximum).
Q.9. What are the causes of ecology alter ?
Ans. (i) Ecospheric Influences :
The ecosphere is the first source of environmental change, since the interactions between the temper, biosphere, hydrosphere, pedosphere and toposphere produce ecology cycles, trends and steady states. Directional changes or trends occur when a threshold within the ecosphere is crossed, merely as what happened when the Antarctic ice expanded during the Late Eocene atmospheric cooling. The ice-'sheet has lasted e'er since through, recently (December 2000) an area of xx,000 sq. miles (51,000 sq. kms) has been satellite- observed as melted! This has caused grave business concern to the environmentalists.
(two) Catholic Influences :
The sunday is the most important source of power of the ecosphere. Steady state changes virtually periodic and quasi-periodic fluctuations are promoted by solar influences. A number of ecospheric processes are finely adjusted to solar cycles. Also some ecospheric processes are attuned to various astronomical pulses, such every bit orbital changes in the dominicus and the planets, the solar system'south passage effectually our galaxy, Milky Way, and the Milk Way's interactions with the neighbouring galaxies. The battery by asteroids and comets may also instigate and encourage biospheric trends.
(three) Geological Influences:
Cycles, steady states and trends in the ecosphere are also produced by geological forces, and the ultimate seat of change lies in the core and drape procedure. The core and mantle processes act through the bureau of the lithosphere. The machinery of plate-tectonics influences body of water-level change, volcanic and mountain building activities, continental drift and true polar wander. Geological changes accept caused long-term bio-diversity trends, since information technology is largely dependent on relative fragmentation of land-masses.
Q.10. Describe the chief constituents of Earth.
Ans. The principal constituents of the earth tin can be considered in four broad groups:
(1) The lithosphere, which is the outer pare of the earth fabricated upwards of rocks and minerals,
(2) The atmosphere, which is the gas or vapor envelope around the earth,
(iii) The hydrosphere, which is the liquid portion of the earth, including the water vapour of the atmosphere, the h2o present in oceans, seas, rivers and lakes, and the water present in rocks, and.
(four) The biosphere, which is the world Of living organisms that dwell on land, in h2o and in the air that nosotros breath.
Q.eleven. What are the different hypotheses regarding the origin of the Earth ?
Ans. From the very starting time, man has been curious to know how the earth and the universe came into being. Due to this mutual interest, all the early civilizations adult their own explanations and versions of the origin of the earth and nature of the universe.
COSMOLOGY is the field of study, which deals with the development of ideas regarding the origin of the earth, its relation to the solar system, and how the solar arrangement is related' to the universe.
Man had to wait until the invention of the telescope, when he could peer into space and explore the universe. However, this could exist done at a express scale. Later two or 3 hundred years, more powerful telescopes were developed. In the concurrently, there had been new developments in the fields of mathematics and physics. These enable homo to explore space more adequately.
There are 2 rival theories explaining the origin of the universe:
(a) The super dense or "BIG BANG" theory:
This theory was put frontwards by Ryle. He suggested that a vast explosion of super dense thing created the universe. This explosion produced the galaxies of stars which are scattered throughout the infinite. The stars are also flying abroad from each other, at the amazing speed of 600 million km/hr.
(b) The steady state or continuous creation theory:
This theory was elaborated by Hoyle, Bondi and Gold. They rejected the Big Blindside Theory. Instead, they put frontwards the idea that matter is being continuously created. New galaxies are built-in and recoup for the ones which are receding beyond man'southward ken.
Q.12. The Mystery Beneath the Crust – Explain !
Ans. When we look up, we can see into infinite for millions of kilometers. Simply, when we endeavour to penetrate downward (by boring) we can only reach down to a land depth of about 4.3 km (14,000 feet). Thus, till today, homo has only been able to scratch the surface of the planet, simply has only penetrated up to such a minute depth — which is fifty-fifty less than 0.001 % of the altitude from the surface to the centre of the earth.
The Mohole Projection was taken upward by American scientists with the aim of improving our knowledge of the sub-crust. The scientists planned to drill a hole, about ten km deep, from the surface, through the crust to the material below. All the same, the project turned out to exist so expensive that it was eventually abandoned after the early piece of work.
Later, much deep sea drilling was washed and cores of sea crust from sites of structural interest were obtained (D.S.D.P. or Deep Sea Drilling Project, and the I.P.O.D. or International Stage of Ocean Drilling Programmes). Valuable data was obtained regarding the behaviour of the earth'southward crust and the rocks beneath.
We do not know exactly what lies beneath and what kind of conditions prevail in the globe's interior. The geologists accept intelligently interpreted the various kinds of prove and tried to tell united states of america about the composition, construction and nature of the earth.
Q.13. How many principal gases are there in the atmosphere ?
Ans. ane. Oxygen (Otwo):
(i) All living organisms inhale Or No life is possible without this gas.
(ii) Information technology can combine with all other elements and thus can class different compounds.
(three) It is indispensable for combustion.
2. Nitrogen (Ntwo):
(i) Its main function in the atmosphere is to dilute oxygen and regulate combustion.
(2) Indirectly, it aids oxidation of dissimilar kinds.
3. Carbon Dioxide (CO2):
(i) Plants inhale this gas.
(ii) Green plants utilize COii in photosynthesis and set their own nutrient.
(iii) It is of swell climatic significance because it efficiently absorbs heat from the upper atmosphere.
(iv) It influences the menses of energy through the atmosphere because CO returns almost half of the absorbed rut dorsum to the earth.
During the by century, big scale fossil fuel called-for has increased the concentration of CO, in the air. Ultimately, this has resulted in the warming of the lower atmosphere.
4. Ozone (O3):
This triatomic form of oxygen is the well-nigh efficient absorber of the scorching ultra-violet radiation from the sun. The ozonosphere protects united states from the ill-effects of excessive quantities of UV rays. The composition of the atmosphere varies with height, latitude and time.
The low-cal gases, peculiarly helium and hydrogen, are found in abundance in the upper atmosphere. Water vapour constitutes almost four% of the atmosphere by volume, but near the surface. In a higher place 10-12 km, it is nearly absent. Ozone is found mainly between 15-35 km, in the Troposphere.
Ozone and water vapour are too the two gases whose concentrations in the atmosphere vary with latitude and season. Ozone content is depression over the Equator (0°). It is high over latitudes north of 50°N, that too mostly during the spring season.
Q. 14. Define Environmental.
Ans. (i) 50. De Vere Burton has defined environmental as:
"The written report of relationships between living organisms and the environments in which they alive is the science of Ecology."
(ii) Co-ordinate to Eugene P. Odum:
"Ecology is the study of the relation of organisms or groups of organisms to their environs, or the science of the interrelations between living organisms and their environment." Therefore, it may be ended that ecology involves the totality of all the reciprocal interactions that have identify between living organisms and their surround.
Q.fifteen. Requite an account of the classification of ecology.
Ans. In that location are several subdivisions of ecology, but only a few important ones have been discussed here.
Scientists have broadly classified ecology into:
(1) Autecology, which involves the written report of one species of organism, and
(two) Synecology, which is the study of communities or unabridged ecosystems.
The following are a few specialized branches of ecology:
(one) Habitat ecology is the ecological study of various habitats on earth and their effects on the organisms living there.
Co-ordinate to the type of habitat under consideration, ecology is further classified into fresh water ecology, marine environmental, grassland ecology, desert environmental etc.
(2) Community ecology:
Is the study of the local distribution of animals in different habitats, the recognition and composition of community units, and succession.
(3) Human ecology:
Also known as population ecology, studies human'southward human relationship with the environment, peculiarly the impact of human behaviour on the environment and the implications of these effects for man.
(four) Applied ecology:
Which is the application of ecological concepts to human needs and requirements, such as woods conservation, animate being husbandry, agriculture, horticulture, wild-life management etc.
(v) Systems ecology:
Which is a relatively modern co-operative of environmental, deals with the analysis and understanding of the part and construction of ecosystems, mainly by using applied mathematics.
Q.16. Define Ecosystem.
Ans. In 1971, Odum divers ecosystem as any unit that included inside information technology all the organisms (i.e. the community) of a given area interacting with the physical surround, and then that a flow of free energy results in a conspicuously defined trophic structure, biotic diversity and textile cycles.
In this context, the post-obit terms need to exist classified:
(a) The trophic structure is the level of nourishment. Plants form the first trophic level, herbivores class the second trophic level and carnivores form the subsequent trophic levels.
(b) Biotic diversity refers to the unlike kinds or types of organisms and their numbers.
(c) Fabric cycles refer to the exchange of materials between living and not-living parts of the system, the transfer of nutrients from one trophic level to another and their re-cyclization.
Q.17. What are the means to conserve forest ?
Ans. With the spread of civilization and the growing demands for forest produce, the world'due south forest comprehend is steadily diminishing by called-for, immigration and felling trees for fuel, or to make space for settlements, agriculture and industry.
Finally, we have realised that forests should not but be preserved for maintaining timber supplies, but also for checking soil erosion, flood, safeguarding water supplies, and for providing recreational facilities.
Nosotros take made a list of ways in which the problems can be overcome:
(1) Afforestment:
Forests felled for timber supply must essentially be replanted with seedling trees. The new trees may non e'er exist the aforementioned as those removed. Many areas which were not forested previously may as well exist planted in order to check soil erosion.
(two) Selective Cutting Practices:
With the aim of better regeneration and survival, the cutting practices should be selective. The weak or diseased species, or the mature species, that are occupying space uselessly, must exist removed. By this method, sufficient trees will remain to forestall soil erosion and the species tin can regenerate at the same fourth dimension.
(3) Clear-cutting Practices:
This is an alternative to selective cutting. Past this method, all the trees are removed, irrespective of age or type. Initially, this may seem to be wasteful. But, if the expanse is replanted, erosion can exist checked. This method is besides cheaper and easier.
(4) Protection of Forests:
Forests should be efficiently protected from natural hazards such equally fires and pests.
In guild to protect forests from fires, there should exist close system of lookout towers and air patrol that tin requite an earliest possible warning. This system is very popular in the United states and Canada.
Forests should exist inspected regularly and sprayed with insecticides in club to fight insects and pests. Insects or animals that prey on the unwanted insect can also introduce into the forest.
(5) Re-utilise of Waste Paper:
Past recycling newsprint and other inferior paper products, timber consumption can exist reduced.
Q.18. What are the uses of h2o ?
Ans. (i) Domestic Water Need:
Under this category is included the various domestic needs, such equally cooking, washing, drinking, cleaning, flushing toilets etc. The consumption of water in any urban center depends on its population.
The minimum charge per unit of domestic consumption of water should exist 70 to 100 liter per capita per mean solar day (lpcd). How this water can be used per head for a boondocks-resident is shown below, but this is totally based on assumption:
The rate of domestic water demand in a urban center is closely associated with the size, economic condition as well every bit non-domestic needs of the city. In rural communities houses do not have water connections, and supply is through hand pumps, wells, tanks etc. Here the water need should be effectually 40 lpcd. But in the few houses with connections, the charge per unit shall exist 70 lpcd, to brand the scheme self-paying.
(ii) Industrial Water Demand :
The industrial demand for water in a town depends on the number, nature and size of industries.
(iii) Institutional Water Need:
Under this category comes the quantity of water needed by various public buildings and institutions. Therefore, since the water is used for public utility purposes, it is former known every bit public demand. Watering of parks and gardens, cleaning streets, roadside fountains and other beautification measures', maintaining public swimming pools and other entertainment centers etc. come nether this kind of demand,
(four) Fire-Fighting Need:
Water is stored for fighting sudden fire-outbreaks. The tanks are filled from nearby h2o bodies by water tankers wherever possible and then used when needed. Loftier-rise buildings (above 25 one thousand height) must be provided with their own h2o storage, other than the water used for domestic purposes,
(v) Unaccounted Use of Water:
A huge quantity of h2o is lost due to thefts, negligence, ignorance etc. Some loss also occurs due to technical issues, such every bit leakages at the joints and valves. Proper vigilance, inspection and timely maintenance can reduce unaccounted loss of water to a large extent.
Q.19. What practise yous mean by waste material h2o ?
Ans. Waste water is defined as a combination of domestic and industrial waste water, with or without rain runoff. Domestic waste water is sewage just and does not include rain runoff. Therefore, waste water is a complex mixture of natural inorganic and organic materials mixed with man-made substances.
It contains everything discharged to the sewer, including materials done from roads, railways and roofs, and, of form, where the sewer is damaged, ground water will besides proceeds entry. In the broadest sense, waste material h2o can exist split up into domestic (sanitary) waste water, also known equally sewage, industrial waste matter water and, finally, municipal waste water which is a mixture of both.
The principal objectives of waste water treatment are:
1. To catechumen the waste materials present in waste water into stable oxidized terminate products. It tin can be safely disposed off to inland water without any adverse ecological furnishings;
2. To protect man health in the society;
3. To recover and recycle the valuable components of waste water;
four. To ensure waste water is effectively disposed off on a regular and reliable ground;
5. To provide an economic method of disposal.
Q.20. Define Water Pollution.
Ans. H2o pollution may be defined as any physical change in the natural water by the addition of any foreign material that adversely affects human and aquatic life, directly or indirectly, in the brusque run or in the long run.
Water is considered to be polluted when it is contaminated with:
(i) Suspended impurities, such as sand, mud, clay and organic matter;
(ii) Dissolved gases like CO2, NHiii, Due northtwo, H2Southward;
(iii) Dissolved minerals like calcium, sodium and magnesium salts;
(4) Isotopes or radio-logically active substances; and
(5) Microorganisms like bacteria, viruses, protozoa'due south and worms.
The pollution of h2o alters the physical properties of water, such equally colour, odor, turbidity and temperature. The presence of dissolved or suspended chemic pollutants tin make the water acidic or saline.
Q.21. What are the sources of water pollution ?
Ans. The principal reasons behind water pollution are the problems like population inpucker, agricultural and industrial waste generation, sewerage disposal, nuclear waste generation, etc.
The sources of water pollution can be of two types:
A. Natural Sources –
(i) Dust:
Soil erosion, volcanic eruption, landslides, storms, earthquakes.
(ii) Gases:
volcanic eruption and expressionless and decaying organic matter.
(iii) Organic Thing:
Decaying bodies of plant and animals in swamps or deep ponds.
(iv) Pelting Water:
Acid rain, specially in industrialized countries.
B. Man-made or Anthropogenic Sources –
(i) Pathogens:
Animal waste and human sewage
(ii) Organic Wastes:
Man and Domestic Sewage, Animal and Found Waste material, Wastes from agro-based industries.
(iii) Inorganic chemicals and minerals:
Agricultural runoff, domestic sewage, animal wastes, wastes from petrochemical, fertilizer and similar other industries, mining activities.
(four) Heat:
Cooling h2o from industrial and power generating installation
(5) Radioactivity:
Nuclear plants.
Q.22. What do you mean by noise pollution ?
Ans. J. Tiffen, an industrial psychologist, has defined it as —
"Noise is a sound which is disagreeable for the individual and which disturbs the normal way of an individual."
According to the Encyclopedia Americana:
"Noise by definition is unwanted sound. What is pleasant to some ears may be extremely unpleasant to others depending on a number of psychological factor. The sweetest music, if it disturbs a person, who is trying to concentrate or to sleep, is a noise to him, just equally the sound of a pneumatic riveting hammer is racket to virtually everyone. In other words any audio may exist racket if circumstances cause it to be agonizing."
We can conclude past saying that any sound which is disagreeable to the individual and which hampers the normal way of the individual is dissonance.
Q.23. What is the meaning of odour pollution ?
Ans. Smell causes distress and discomfort, while odour, under different weather condition, tin exist pleasing. The osmogenic molecules (odor) enter the nasal cavity through the nostrils. They excite the osmoceptors. The specific impulse travels forth the myelinated nerve fibers to the receptor centres in the brain in the class of specific electric discharges.
The message is. processed and delivered to the evaluation centres in the brain. Here olfactory information is compared with stored experience (the retentivity), and finally the estimation of message is relayed back along other nerve paths.
Q.24. Discuss the sources of odour pollution.
Ans. Stale air is characteristic of areas that are populated or overpopulated — whether residential, commercial or industrial. Stale air is deprived of its full oxygen value.
Instead, it carries a considerable surplus of carbon dioxide:
(i) Perspiration is probably the almost common metabolic sources of odours. A worker in a hot and boiling environment is, likely to lose up to 900 g sweat per hour. Normal sweat from a good for you person does not accept any particular olfactory property.
Information technology becomes repulsive when the urea content (usually about 0.03%) or butyric acid (normally nigh 0.001%) increases slightly. Sometimes sweat also contains valeric acid, which, in combination with butyric acrid, forms the characteristic body aroma.
(two) Various diseases may also create scent and pollute the air, such equally cancer in advanced stages, tinea versicolor, osteomyelitis, ozaena etc.
(3) Certain pathological weather, such as bromidrosis produced by decomposing keratin of the feet, are characterized by offensively smelling sweat.
(4) Stale or fermented urine smells of ammonia besides equally cyclohexene-3-one.
(v) The odours of the alimentary tract are dependent upon the blazon of digestion taking place. Stools give off highly offensive smells when they are alkaline, indicating protein putrefaction.
(half dozen) Objectionable cooking odour originates from the production of sulphur compounds together with steam — while cooking vegetable or animal matter.
(vii) Industries give off various kinds of smells, according to the type of solvent used for the numerous natural and synthetic materials employed in the finishing trade.
Solvent vapours are extremely volatile and give rise to photochemical smog.
Q.25. What are the measures to control olfactory property pollution ?
Ans. (i) The concentration of odour in houses, schools, role, factories etc. must be checked one time in a calendar month and controlled when necessary.
(2) The sudden outbreaks of steam smoke and other odour-producing fumes must be controlled.
(iii) A mobile laboratory fitted with a radio telephone transmitter and receiver for communication is needed to check the odoriferous dusts and fumes.
(iv) In localities around industrial areas, the concentration of oxides of carbon, nitrogen, sulphur and other pollutants must be evaluated every half an hour.
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