BOND ENTHALPY IN THE FORM OF BOND ENERGY

BOND ENTHALPY IN THE FORM OF BOND ENERGY This article envisages bond enthalpies in the form of bond energies and looks at some simple calculations involving them. One of the most confusing things about this is the way the words are used. These days, the term "bond enthalpy" is normally used, but we will also find it described as "bond energy" - sometimes in the same article. An even older term is "bond strength". So we can take all these terms as being interchangeable. As we will see below, though, "bond enthalpy" is used in several different ways, and we might need to be careful about this.
Explaining the terms Bond dissociation enthalpy and mean bond enthalpy indicate Simple diatomic molecules A diatomic molecule contains only two atoms. They could be the same (for example, Cl2) or different (for example, HCl). The bond dissociation enthalpy is the energy needed to break one mole of the bond to give separated atoms, everything being in the gas state. The point about everything being in the gas state is essential.  We cannot use bond enthalpies to do calculations directly from substances starting in the liquid or solid state. As an example of bond dissociation enthalpy, to break up 1 mole of gaseous hydrogen chloride molecules into separate gaseous hydrogen and chlorine atoms takes 432 kj. The bond dissociation enthalpy for the H-HCl bond is +432 kj mol-1. More complicated molecules What happens if the molecule has several bonds, rather than just 1? Consider methane, CH4. It contains four identical C-H bonds, and it seems reasonable that they should all have the same bond enthalpy. However, if you took methane to pieces one hydrogen at a time, it would need a different amount of energy to break each of the four C-H bonds. Every time you break a hydrogen off the carbon, the environment of those left behind changes. And the strength of a bond is affected by what else is around it. In cases like this, the bond enthalpy quoted is an average value. In the methane case, you can work out how much energy is needed to break a mole of methane gas into gaseous carbon and hydrogen atoms. That comes to +1662 kj and involves breaking 4 moles of C-H bonds. The average bond energy is therefore +1662/4 kj, which is +415.5 kj per mole of bonds. That means that many bond enthalpies are actually quoted as mean (or average) bond enthalpies, although it might not actually say so. Mean bond enthalpies are sometimes referred to as "bond enthalpy terms". In fact, tables of bond enthalpies give average values in another sense as well, particularly in organic chemistry. The bond enthalpy of, say, the C-H bond varies depending on what is around it in the molecule. So, data tables use average values, which will work well enough in most cases. That means that if you use the C-H value in some calculation, you can't be sure that it exactly fits the molecule you are working with. So don't expect calculations using mean bond enthalpies to give very reliable answers. You may well have to know the difference between a bond dissociation enthalpy and a mean bond enthalpy, and you should be aware that the word mean (or average) is used in two slightly different senses. But for calculation purposes, it isn't something you need to worry about. Just use the values you are given.
. Remember that you can only use bond enthalpies directly if everything you are working with is in the gas state. Using the same method as for other enthalpy sums We are going to estimate the enthalpy change of reaction for the reaction between carbon monoxide and steam. This is a part of the manufacturing process for hydrogen. The bond enthalpies are: bond enthalpy (kJ mol-1) C-O in carbon monoxide +1077 C-O in carbon dioxide +805 O-H +464 H-H +436 So let's do the sum. Here is the cycle - make sure that you understand exactly why it is the way it is. And now equate the two routes, and solve the equation to find the enthalpy change of reaction. ΔH + 2(805) + 436 = 1077 + 2(464) ΔH = 1077 + 2(464) - 2(805) - 436 ΔH = -41 kJ mol-1 Using a shortcut method for simple cases You could do any bond enthalpy sum by the method above, taking the molecules completely to pieces and then remaking the bonds. If you are happy doing it that way, just go on doing it that way. However, if you are prepared to give it some thought, you can save a bit of time, although only in very simple cases where the changes in a molecule are very small. For example, chlorine reacts with ethane to give chloroethane and hydrogen chloride gases. (All of these are gases. I have left the state symbols out this time to avoid cluttering the diagram.) It is always a good idea to draw full structural formulae when you are doing bond enthalpy calculations. It makes it much easier to count up how many of each type of bond you have to break and make. If you look at the equation carefully, you can see what I mean by a "simple case". Hardly anything has changed in this reaction. You could work out how much energy is needed to break every bond, and how much is given out in making the new ones, but quite a lot of the time, you are just remaking the same bond. All that has actually changed is that you have broken a C-H bond and a Cl-Cl bond, and made a new C-Cl bond and a new H-Cl bond. So you can just work those out. bond enthalpy (kJ mol-1) C-H +413 Cl-Cl +243 C-Cl +346 H-Cl +432 Work out the energy needed to break C-H and Cl-Cl: +413 + 243 = +656 kJ mol-1 Work out the energy released when you make C-Cl and H-Cl: -346 - 432 = -778 kJ mol-1 So the net change is +656 - 778 = -122 kj mol-1
Cases where we have a liquid present I have to keep on saying this! Remember that you can only use bond enthalpies directly if everything you are working with is in the gas state. If you have one or more liquids present, you need an extra energy term to work out the enthalpy change when you convert from liquid to gas, or vice versa. That term is the enthalpy change of vaporisation, and is given the symbol ΔHvap or ΔHv. This is the enthalpy change when 1 mole of the liquid converts to gas at its boiling point with a pressure of 1 bar (100 kPa). (Older sources might quote 1 atmosphere rather than 1 bar.) For water, the enthalpy change of vaporisation is +41 kj mol-1. That means that it takes 41 kj to change 1 mole of water into steam. If 1 mole of steam condenses into water, the enthalpy change would be -41 kj. Changing from liquid to gas needs heat; changing gas back to liquid releases exactly the same amount of heat. To see how this fits into bond enthalpy calculations, we will estimate the enthalpy change of combustion of methane - in other words, the enthalpy change for this reaction: Notice that the product is liquid water. You cannot apply bond enthalpies to this. You must first convert it into steam. To do this, you have to supply 41 kj mol-1. The bond enthalpies you need are: bond enthalpy (kJ mol-1) C-H +413 O=O +498 C=O in carbon dioxide +805 O-H +464 The cycle looks like this: This obviously looks more confusing than the cycles we've looked at before, but apart from the extra enthalpy change of vaporisation stage, it isn't really any more difficult. Before you go on, make sure that you can see why every single number and arrow on this diagram is there. In particular, make sure that you can see why the first 4 appears in the expression "4(+464)". That is an easy thing to get wrong. (In fact, when I first drew this diagram, I carelessly wrote 2 instead of 4 at that point!) That's the hard bit done - now the calculation: ΔH + 2(805) + 2(41) + 4(464) = 4(413) + 2(498) ΔH = 4(413) + 2(498) - 2(805) - 2(41) - 4(464) ΔH = -900 kJ mol-1 The measured enthalpy change of combustion is -890 kj mol-1, and so this answer agrees to within about 1%. As bond enthalpy calculations go, that's a pretty good estimate.

Yaba culture, a new threat on youths

There is no denying the fact that presently, the young groups are being habituated day by day in taking yaba and push them into the murky world from where; there is little chance to come back in normal life. When a person is obsessed to such toxic drug, some changes appear gloomily in his normal activities in his whole physical state of affairs. Some changes may happen in his overall mental physique; he cannot sleep at night, he talks in a meaningless way, he feels intense headache and diminutive hunger, his hallucination and thought turn hazy where all of them result from break down of nervous system and damage of neuron bound step by step. Virtually, such symptoms are not the actual symptoms of a man who enjoys sound body as well as sound mind. Suffice it to say, feeling sickness every time may be collectively presumed as the characteristics of yaba infected persons. With taking yaba, people become physically and mentally sick and as such, after being addicted, they behave abnormally like being jealousy, crazy, hypocrite and mentally being disrobed, he cannot behave like a healthy man; rather, his attitude and feelings turn into a strange dealing by his flow of movement, talking, walking and his general pattern of life. Such behavioral patterns indicate the dealings like lower animals of neurotic creatures, far away from human beings. For this reason, the vigorous society believes that the resources of the drug aficionado person have been robbed and he has been well-groomed over night.

It is obvious that being addicted in such dreadful drugs they may be inclined to behave like the smart boy who is bedded on wrong conception on stylishness and personality. Elegance originates from the principle of integrity, faith, justice and tranquility. They are usually found committing mistakes in defining elegance and chic. They develop a passion for it and make it a style without considering any negative effects in future. It bestows them impulsive elation in their life and they are found slowly but surely absorbed in it. The inventiveness of insidious know-how spreads rapidly like pestilence through rake associations. It is too late however when they become conversant with the toxic effects and new concepts begin to flourish in their survival due to machination as a new invention of pleasing and exciting aspects. Eventually, they do not find any way to get rid of and the search for tidiness thus ends in the canopy passageway of obliteration. Such fatal consequences take place when the young men are not guided properly. When the high-class particularly parents and teachers keep aloof themselves from being infected, the subordinate groups lead their efforts into their own decisions without much speculation. They slither in the drug fence in as there is no one to tip off them. Taking plus of the situation, the mafia ogre with their influential words make the gullible boys and girls their easy victim ; so the cavernous detachment  between parents and progeny, teachers and young learners irrespective of caste and creed, are also liable  on a large scale for the yaba hazard ingrained in social and cultural tradition. The letdown of the youths in building a good preference is the partial drawback of the superiors and advisors in carrying out their own errands.

Therefore, it is noteworthy that they are one way or another distorted to take drugs like Yaba, heroine, chorus, phencidel, wine cigarettes, alcohol and many other infatuated materials awfully detrimental for vigor and hygiene. When a person leaves optimism of life, he thinks that drug addiction is only the way without which he cannot live to tell the tale on earth and as such in the next course of action, he takes drugs after drugs and become captivated. When in one time, he becomes irritated; he cannot give up those addictions because he remains in the state of phantasm and sensitively malformed.  Hence, alcoholics do not drink minimally for gratification, but because they assume that they cannot face life's problems ingrained in blood and bone without alcohol. In order to get rid of such hurdles, he or she should devote to work with sincere attention and painstaking attitude. He or she should take physical exercise in the form of meditation and religion. He or she needs to be truthful, credulous and ideal based on simple living and high thinking to get involved in how to lead life controlled and cleanly.

The Pollutions around us

A substance may be a contaminant when its occupancy in air, water, or soil harms organism in question is predominant and as such bacteria and virus carriers such minute living thing can cause contamination in a significant manner. Pollutants harm humans in different ways where in high concentrations they can cause ill health and even death. These sort of pollutants which are horrifying in due sense can spread through food chains spoiling plants and animals and endangering human food supplies like fish, and they can cause dirt and obnoxious smells.

Atmospheric pollution

The principal inception of air contamination are the burning of coal and oil in houses and factories, and in the engines of cars, buses, airplanes and thus smoke assembled by burning contains small particles of dust which are mainly carbon. This dust calumniates the walls of the buildings and settles on the leaves of plants, limiting photosynthesis by cutting out light and limiting materialization by blocking stomata. Smoke contains sulphur dioxide that reacts with water vapour in air forming sulphuric acid causing damages the stonework of buildings, the leaves of plants, and the peoples lungs which vitally important for controlling breathing function. Garden bonfires can also be a source of hazardous pollution. If household rubbish including plastic and polystyrene is added to the fire, its smoke will contain up to 300 times more cancer-producing chemicals than cigarettes smoke, as well as cyanide, lead, dioxin, and other poisonous chemicals. There is no denying the fact that Petrol and diesel engines release fumes containing oxides of nitrogen and lead compounds. Once lead enters the body it cannot be removed by the excretory system. It collects in the body eventually causing damage, especially on the brain.

Mellifluous Pollution

The main source of water pollution is sewage from houses and farms, chemical waste from industry and agriculture, and spilled oil. Sewage can be made harmless but in many countries population growth has overloaded sewage handling works and untreated sewage is released into rivers and sea. Bacteria in water disintegrate sewage, but in lakes and slow-moving rivers this process uses up oxygen so briskly that fish, insects, and tadpoles, are missing. Industrial waste often manifests very venomous, long-lasting pollutants such as composites of cyanide, lead mercury, and mercury, and copper. These chemicals are jeopardous even in small cornucopia, because when they are discharged into streamlet and rivulet, they garner fish and other aquatic creatures. In this way these are amplified through food chains to water birds and sometimes humans.

In many recent farms poultry, cattle, and pigs are possessed in buildings and there is no other land on which to use the fertilizer that they produce. The manure is released into local streams and rivers where it decomposes and reduces oxygen levels in the same way as untreated domestic sewage. Other pollutants attributable to modern farming methods include chemical sprays that kill insect pests and fungi that skirmish crop plants. If these chemicals enter rivers and ponds they can spread through out food chains in the same way as industrial waste.

Dispersion

Radiation such as X-rays and beta and gamma rays can cause various types of cancer, a blood disorder known as leukemia, and damage to the sperms and ova resulting in deformed babies. Natural radiation comes from outer space in the form of cosmic rays, and artificial radiation comes from certain medical and industrial processes. Little if any harm comes from these sources; but there is increasing concern about radiation from the testing of nuclear power to generate electricity will increase. There is always a risk in emitting radiation upon the surface where it is falling. The persons, who are always dealing radiation as routine job and research purpose, they need to be careful about such fission and fusion phenomena. If air is polluted by radiation, environment must be polluted in question and consequently many dreadful diseases may break out.

Meteorological pollution:

There are many ranges of barometric pollution problems currently alarming the earth's general environment; the problem arises from the acidic gases produced by burning fossil fuels in a different situations. The majority of power stations in industrialized countries burn coal or oil. Both these fuels are polluted with sulphur, which produces sulphur dioxide when it burns. The wind can carry acid rain clouds away from the industrialized centers, causing the pollution to fall on other countries. Besides this, oxides of Nitrogen dioxide are produced when thunderstorm blows or air are heated in furnaces or in vehicle petrol engines. Consequently, these gases dissolve in rainwater to produce acid rain. Due to acid rain, the following adverse effects are observed:

·         Limestone buildings and statues are worn away.

·         Lakes and rivers are acidified, and the presence of metal ions leached out of the soil damages the gills of the fish and as such the fishes can die.

·         The nutrients are leached out of the soil and from leaves. Trees are deprived of these nutrients. Aluminum ions are freed from the clay as Aluminum sulphate and damage the roots of the trees. The tree is unable to draw up water through damaged roots and it dies. Due to depletion of ozone layer, a protective layer of ozone in the stratosphere prevents harmful ultra-violet radiation reaching the earth surface ozone layer remains depleted.

·         Chlorofluorocarbons and other halogen compounds are formed due to the depletion of ozone layer, which causes the damage of human beings and plants in question, for which restrictions have been imposed to use such compounds virtually by International agreement.

In view of the above it is evident that if the situation were tolerable to grow worse, preamble to higher levels of ultra-violet radiation could effect more cases of skin cancer in human and cause crops to a great extent. That is to say, in burning chemicals and bricks, poisonous gas emit and as such sulphur dioxide gas, Nitrogen dioxides and carbon monoxide gas are produced in atmospheric layer and consequently, acid rain occurs. This sort of acid rain causes trees to destroy and soil to pollute and poisonous. 

As a result of creating such dangerous pollutants, our lives are becoming risky and health hazards. Besides this, the problems of green house effects are throughout the world for which we should find out ways and means to solve the impediments, which create health exposure in our every day life. The CFC gas is the product of tremendous effects of greenhouse chattels and as a result, our environment is being polluted creating great health vulnerability in question. The fact is that due to awesome increase of CFC gas and carbon dioxide, ozone layer is consequently licked and the ultra-violet ray from the Ionosphere is in the way to hit the earth directly for which the surface temperature is gradually increasing and the ice is melted and the depth of the sea is also being increased. It is hoped in future that in course of time, the earth will be inundated under water. It has been observed in recent years survey that due to tremendous indiscriminate use of ploy-ethane bags, pollution are occurring to a great extent. In the world, wastage is being observed but these are being recycled in a developed process, which are the consequences of better technology and scientific research. In order to remove such pollution, a better technology and strong recycling process are needed for which new bags are possible to be made. 

Besides this, we need to be careful about dealing wastage for which prospective and alternative measures are keenly emphasized in a systematic manner. We know that the plants and trees are vitally important in order to make our environments healthy and sophisticated to live peacefully in the world. On the other hand, due to lack of trees, adverse situations prevail in the atmospheric layer like increasing carbon dioxide and dust particles. If this type of gas is increased in the layer, our environment becomes barren and unsuitable for living. We use oxygen in our inhalation and give out carbon dioxide as a general flow of breathing function. Trees give us shadow and fruits for which our survival on earth becomes easy and comfortable. We need trees in order to make our environment free from pollution. 

Hence, it is widely recognized that due to enormous use of plants and trees, we are always facing the situations of health hazard and for which the government is careful to plant trees in place of the trees cut down. Since the plants and trees are being cut down to a great extent, the amount of lands have been reducing day by day for which the scarcity of cultivable lands are being observed tremendously. As a result of being extinct the forests, the number of animals, birds and other creature living in woodland are being reduced to a great extent. The main weapon to fight against extinction is self-awareness and consciousness. It has to come within everybody that we have to possess the feelings of responsibility and environmentalism, in order to build a better world -a world full of evergreen beauty and spirited animals and for these purpose, the following steps may be taken in due course.

·         Following and whaling should be absolutely proscribed

·         Deforestation needs to be counteracted

·         The use of ivory and furs needs to be declared as a punishable crime imposing an exemplary penalty in question.

·         National parks and nature reserves should be created

·         The natural habitats of endangered species should be preserved.

If these tactics of measures are accomplished instantaneously, then it may be anticipated an optimistic upshot that a man can see the dawn of a new era in the history of the world, which will be even more eye-catching if we are engrossed to be humiliated with one another by forsaking all sorts of enmity and quarrelsome activities from the social life.

The history of Mughal Territory In Indo-subcontinent

There is no denying the fact that the Mughal Territory was adominion that at its paramount defensive extended ruled parts of what is today's Afghanistan, Pakistan and most of the Indian Subcontinent, then known as Hindustan, between 1526 and 1707. The realm was founded by the Timurid forerunner Babur in 1526, when he defeated Ibrahim Lodi, the last of the Delhi Sultans at the First Scuffle of Panipat. "Mughal" is the Persian word for "Mongol". The religion of the Mughals was Islam and based on the faith upon God, the ruling system was promulgated in the form of administration and defense as a tentative flow. The terrain was generally subjugated by the Afghan Sher Shah Suriin the course of the time of Humayun, the second Mughal monarch, but under Akbar it grew considerably, and sustained to grow until the end of Aurangzeb's rule. Jahangir, the son of Akbar, ruled the empire between 1605–1627. In October 1627, Mughal Emperor Shah Jahan, son of Jahangir, "flourished to the throne", where he "inherited a vast and rich empire" in India; and "at mid-century this was perhaps the greatest empire in the world". Shah Jahan bespoke the famous TajMahal (amid 1630–1653), in Agra. The Mughals faced stiff competition from the Marathas, and after Aurangzeb died in 1707, the empire started to decline in actual power, giving way to the rise of the Hindu Maratha Empire. The Mughals however managed to maintain some trappings of power in the India for another 150 years. In 1739 it was defeated by an army from Persia led by Nadir Shah. In 1756 an army of Ahmed Shah Abdali took Delhi again. The British Empire finally dissolved it in 1857, immediately prior to which it existed only at the sufferance of the British East India Company. Faith The Mughal ruling class was liberal-minded Muslims, even thoughfurthermost of the subjects of the Empire were Hindu. Though Babur established the Empire, the empire remained unstable (and was even exiled) until the reign of Akbar, who was not only of liberal disposition but also intimately acquainted, since birth, with the mores and traditions of India. Under Akbar's rule, the court abolished the jizya (the poll-tax on non-Muslims) and abandoned use of the lunar Muslim calendar in favor of a solar calendar more useful for agriculture. One of Akbar's most unusual ideas regarding religion was Din-i-Ilahi ("Faith-of-God" in English), which was an eclectic mix of Hinduism, panthiestic versions of Sufi Islam,Zoroastrianism and Christianity. It was proclaimed the state religion until his death. These actions however met with stiff opposition from the Muslim clergy. However, the orthodoxy regained influence only three generations later, with Aurangzeb, known for upholding doctrines of orthodox Islam; this last of the Great Mughals retracted nearly all the liberal policies of his forbears.  Mughal Sovereigns Emperor Reign start Reign end Babur 1526 1530 Humayun 1530 1540 Interregnum * 1540 1555 Humayun 1555 1556 Akbar 1556 1605 Jahangir 1605 1627 Shah Jahan 1627 1658 Aurangzeb 1658 1707 Formation and supremacy of Babur In the early 16th century, Muslim armies consisting of Mongol, Turkic, Persian, and Afghan warriors invaded India under the leadership of the Timurid prince Zahir-ud-Din-Mohammad Babur. Babur was the great-grandson of Mongol conqueror TimurLenk (Timur the Lame, from which the Western name Tamerlane is derived), who had invaded India in 1398 before retiring to Samarkand who himself claimed descent from the Mongol ruler, Genghis Khan. Babur was driven from Samarkand by the Uzbeks and initially established his rule in Kabul in 1504. Later, taking advantage of internal discontent in the Delhi sultanate under Ibrahim Lodi, and following an invitation from Daulat Khan Lodi (governor of Punjab) and Alam Khan (uncle of the Sultan), Babur invaded India in 1526. Babur, a seasoned military commander, entered India in 1526 with his well-trained veteran army of 12,000 to meet the sultan's huge but unwieldy and disunited force of more than 100,000 men. Babur defeated the Lodi sultan decisively at the first Battle of Panipat. Employing gun carts, moveable artillery, and superior cavalry tactics, Babur achieved a resounding victory and the Sultan was killed. A year later (1527) he decisively defeated, at the battle of Khanwa, a Rajput confederacy led by RanaSanga of Chittor. A third major battle was fought in 1529 when, at the battle of Gogra, Babur routed the joint forces of Afghans and the sultan of Bengal. Babur died in 1530 at Agra before he could consolidate his military gains. He left behind as his chief legacy a set of descendants who would fulfill his dream of establishing an empire in the Indian subcontinent. Early Sikh Gurus' perception of the Mughal Empire Babur's reign was witnessed by the first Sikh Guru Nanak DevJi. His RaagAsa Guru records Nanak's observations and thoughts in his poems. It says: "Having attacked Khuraasaan, Babar terrified Hindustan. The Creator Himself does not take the blame, but has sent the Mugal as the messenger of death. There was so much slaughter that the people screamed. Didn't You feel compassion, Lord?" Hindu women in Babur's rule: "Those heads garlanded with interweavedmop, with their parts highlighted with vermilion - those heads were shaved with scissors, and their throats were choked with dust.They lived in regalmanors, but now, they cannot even sit near the palaces.... ropes were put around their necks, and their strings of pearls were broken. Their wealth and youthful beauty, which gave them so much pleasure, have now become their enemies. The order was given to the soldiers, who dishonored them, and carried them away. If it is pleasing to God's Will, He bestows greatness; if is pleases His Will, He bestows punishment" Mughal rule under Babur: "First, the tree puts down its roots, and then it spreads out its shade above. The kings are tigers, and their officials are dogs; they go out and awaken the sleeping people to harass them. The public servants inflict wounds with their nails. The dogs lick up the blood that is spilled." Source: Rag Malar, (pg.1288) Strangely enough, the land on which the Sikh Golden temple now stands, was actually donated by Mughal emperor Akbar. Reign of Humayun When Babur died, his son Humayun (1530–56) inherited a difficult task. He was pressed from all sides by a reassertion of Afghan claims to the Delhi throne and by disputes over his own succession. He fled to Persia, where he spent nearly ten years as anhumiliated guest of the Safavid court of Shah Tahmasp. During Sher Shah's reign, an imperial unification and administrative framework were established; this would be further developed by Akbar later in the century. In 1545, Humayun gained a foothold in Kabul with Safavid assistance and reasserted his Indian claims, a task facilitated by the weakening of Afghan power in the area after the death of Sher Shah Suri in May 1545. He took control of Delhi in 1555, but died within six months of his return, from a fall down the steps of his library. Sway of Akbar Humayun's premature death in 1556 leftward the task of takeover and magnificentamalgamation to his thirteen-year-old son, Jalal-ud-Din Akbar. Following a decisive military victory at the Second Battle of Panipat in 1556, the regent Bayram Khan pursued a vigorous policy of expansion on Akbar's behalf. As soon as Akbar came of age, he began to free himself from the influences of overbearing ministers, court factions, and harem intrigues, and demonstrated his own capacity for judgment and leadership. A workaholic who seldom slept more than three hours a night, he personally oversaw the implementation of his administrative policies, which were to form the backbone of the Mughal Empire for more than 200 years. He continued to conquer, annex, and consolidate a far-flung territory bounded by Kabul in the northwest, Kashmir in the north, Bengal in the east, and beyond the Narmada River in central India. Akbar assembled a enveloped capital called FatehpurSikri  near Agra, starting in 1571. Strongholds for each of Akbar's senior queens, a huge artificial lake, and sumptuous water-filled courtyards were built there. However, the city was soon abandoned and the capital was moved to Lahore in 1585. The reason may have been that the water supply in FatehpurSikri was inadequate or of poor quality; or, as some historians believe, that Akbar had to attend to the northwest areas of his empire and therefore moved his capital northwest. In 1599, Akbar shifted his capital back to Agra from where he reigned until his death. Akbar adopted two distinct but effective approaches in administering a large territory and incorporating various ethnic groups into the service of his realm. In 1580 he obtained local revenue statistics for the previous decade in order to understand details of productivity and price fluctuation of different crops. Aided by Todar Mal, a hindu scholar, Akbar issued a revenue schedule that optimised the revenue needs of the state with the ability of the peasantry to pay. Revenue demands, fixed according to local conventions of cultivation and quality of soil, ranged from one-third to one-half of the crop and were paid in cash. Akbar relied heavily on land-holding zamindars to act as revenue-collectors. They used their considerable local knowledge and influence to collect revenue and to transfer it to the treasury, keeping a portion in return for services rendered. Within his administrative system, the warrior aristocracy (mansabdars) held ranks (mansabs) expressed in numbers of troops, and indicating pay, armed contingents, and obligations. The warrior aristocracy was generally paid from revenues of nonhereditary and transferable jagirs (revenue villages). An astute ruler who genuinely appreciated the challenges of administering so vast an empire, Akbar introduced a policy of reconciliation and assimilation of Hindus (including Jodhabai, later renamed Mariam-uz-Zamani begum, the Hindu mother of his son and heir, Jahangir), who represented the majority of the population. He recruited and rewarded Hindu chiefs with the highest ranks in government; encouraged intermarriages between Mughal and Rajput aristocracy; allowed new temples to be built; personally participated in celebrating Hindu festivals such as Deepavali, or Diwali, the festival of lights; and abolished the jizya (poll tax) imposed on non-Muslims. Akbar came up with his own theory of "rulership as a divine illumination," enshrined in his new religion Din-i-Ilahi (Divine Faith), incorporating the principle of acceptance of all religions and sects. He encouraged widow re-marriage, discouraged child marriage, outlawed the practice of sati, and persuaded Delhi merchants to set up special market days for women, who otherwise were secluded at home. By the end of Akbar's reign, the Mughal Empire extended throughout north India even south of the Narmada river. Notable exceptions were Gondwana in central India, which paid tribute to the Mughals, Assam in the northeast, and large parts of the Deccan. The area south of the Godavari river remained entirely out of the ambit of the mughals. In 1600, Akbar's Mughal empire had a revenue of £17.5 million. By comparison, in 1800, the entire treasury of Great Britain totaled £16 million. Akbar's empire supported vibrant intellectual and cultural life. The large imperial library included books in Hindi, Persian, Greek, Kashmiri, English, and Arabic, such as the Shahnameh, Bhagavata Purana and the Bible. Akbar regularly sponsored debates and dialogues among religious and intellectual figures with differing views, and he welcomed Jesuit missionaries from Goa to his court. Akbar directed the creation of the Hamzanama, an artistic masterpiece that included 1400 large paintings. Reigns of Jahangir and Shah Jahan Mughal rule under Jahangir (1605–27) and Shah Jahan (1628–58) was noted for political stability, brisk economic activity, beautiful paintings, and monumental buildings. Jahangir married a Persian princess whom he renamed NurJehan (Light of the World), who emerged as the most powerful individual in the court besides the emperor. As a result, Persian poets, artists, scholars, and officers--including her own family members--lured by the Mughal court's brilliance and luxury, found asylum in India. The number of unproductive officers mushroomed, as did corruption, while the excessive Persian representation upset the delicate balance of impartiality at the court. Jahangir liked Hindu festivals but promoted mass conversion to Islam; he persecuted the followers of Jainism and even executed Guru ArjunDev, the fifth saint-teacher of the Sikhs in 1606 for refusing to make changes to the Guru Granth Sahib (the Sikh holy book). The execution was not entirely for religious reasons; Guru ArjunDevJi supported Prince Khusro, another contestant to the Mughul throne in the civil war that developed after Akbar's death. Noor Jahan's abortive efforts to secure the throne for the prince of her choice led Shah Jahan to rebel against Jahangir in 1622. In that same year, the Persians took over Kandahar in southern Afghanistan, an event that struck a serious blow to Mughal prestige. Between 1636 and 1646, Shah Jahan sent Mughal armies to conquer the Deccan and the lands to the northwest of the empire, beyond the Khyber Pass. Even though they aptly demonstrated Mughal military strength, these campaigns drained the imperial treasury. As the state became a huge military machine, causing the nobles and their contingents to multiply almost fourfold, the demands for revenue from the peasantry were greatly increased. Political unification and maintenance of law and order over wide areas encouraged the emergence of large centers of commerce and crafts--such as Lahore, Delhi, Agra, and Ahmadabad--linked by roads and waterways to distant places and ports. The world-famous TajMahal was built in Agra during Shah Jahan's reign as a tomb for his beloved wife, MumtazMahal. It symbolizes both Mughal artistic achievement and excessive financial expenditures at a time when resources were shrinking. The economic positions of peasants and artisans did not improve because the administration failed to produce any lasting change in the existing social structure. There was no incentive for the revenue officials, whose concerns were primarily personal or familial gain, to generate resources independent of what was received from the Hindu zamindars and village leaders, who, due to self-interest and local dominance, did not hand over the entirety of the tax revenues to the imperial treasury. In their ever-greater dependence on land revenue, the Mughals unwittingly nurtured forces that eventually led to the break-up of their empire. Reign of Aurangzeb and decline of empire The last of the great Mughals was Aurangzeb. During his fifty-year reign, the empire reached its greatest physical size but also showed unmistakable signs of decline. The bureaucracy had grown corrupt; the huge army used outdated weaponry and tactics. Aurangzeb restored Mughal military dominance and expanded power southward, at least for a while. Aurangzeb was involved in a series of protracted wars: against the Pathans in Afghanistan, the sultans of Bijapur and Golkonda in the Deccan, the Marathas in Maharashtra and the Ahoms in Assam. Peasant uprisings and revolts by local leaders became all too common, as did the conniving of the nobles to preserve their own status at the expense of a steadily weakening empire. The increasing association of his government with Islam further drove a wedge between the ruler and his Hindu subjects. Contenders for the Mughal throne were many, and the reigns of Aurangzeb's successors were short-lived and filled with strife. The Mughal Empire experienced dramatic reverses as regional nawabs or governors broke away and founded independent kingdoms. In the war of 27 years from 1680 to 1707, the Mughals suffered several heavy defeats at the hands of the Marathas. They had to make peace with the Maratha armies, and Persian and Afghan armies invaded Delhi, carrying away many treasures, including the Peacock Throne in 1739. The first Mughal emperor Babur wrote in his diary TuzkBabri: "Hindustan is a country which has few pleasures to recommend it.... Indians have no idea of the charms of friendly society, of frankly mixing together, or of familiar intercourse.... They have no horses, no good grapes, or musk melons, no good fruits, no ice or cold water, no good food or bread in their bazaars, no bath or colleges, no candles, no torches, not a candle stick." The Mughals were superior to their Indian counterparts in war but also considered themselves so culturally. They had taste for the fine things in life - for beautifully designed artifacts and the enjoyment and appreciation of cultural activities. However, the Hindus of India provided the Mughals with a richer philosophy and the plentiful spices and vegetarian options which were incorporated into modern Indian life. While the Mughals' superior position may have been appreciated, in reality, they probably borrowed as much as they gave. However, it could not be doubted that they introduced many changes to Indian society and culture, including: Centralized government which conveyedcollected many smaller kingdoms Delegated government with respect for human rights Persian art and culture amalgamated with native Indian art and culture Started new trade routes to Arab and Turk lands Mughal cuisine Urdu and Hindi languages were formed for common Muslims and Hindus correspondingly Periods of great religious broadmindedness A style of construction Landscape horticulture A system of education that took account of pupils' needs and culture

            In view of the above, it is evident that the Mughal Empire had continued their efforts to beautify this subcontinent in a significant manner by extending their pelf and power and knowledge based on modern thoughts and intellectuals. Not only in the field of science and technology but also in overall atmosphere of structural world, are their achievements ever memorable in the history of the world.