According to .........., the properties of elements are a periodic function of their atomic masses. ?->(Show Answer!)

1. According to .........., the properties of elements are a periodic function of their atomic masses.

Write Comment

Comments

Tags

Show Similar Question And Answers

QA->In the periodic table of elements, the noble gases are arranged in the ?....

QA->Materials for rain-proof coats and tents owe their water proof properties to:....

QA->When do all the magnetic materials lose their magnetic properties?....

QA->Name the economy in which people work according to the principle ‘from each according to his ability to each according to his needs’?....

QA->Whichelement with atomic number 113 in the Periodic Table has become the first everelement to be discovered by an Asian country (Japan)?....

MCQ-> Since World War II, the nation-state has been regarded with approval by every political system and every ideology. In the name of modernisation in the West, of socialism in the Eastern bloc, and of development in the Third World, it was expected to guarantee the happiness of individuals as citizens and of peoples as societies. However, the state today appears to have broken down in many parts of the world. It has failed to guarantee either security or social justice, and has been unable to prevent either international wars or civil wars. Disturbed by the claims of communities within it, the nation-state tries to repress their demands and to proclaim itself as the only guarantor of security of all. In the name of national unity, territorial integrity, equality of all its citizens and non-partisan secularism, the state can use its powerful resources to reject the demands of the communities; it may even go so far as genocide to ensure that order prevails.As one observes the awakening of communities in different parts of the world, one cannot ignore the context in which identity issues arise. It is no longer a context of sealed frontiers and isolated regions but is one of integrated global systems. In a reaction to this trend towards globalisation, individuals and communities everywhere are voicing their desire to exist, to use their power of creation and to play an active part in national and international life.There are two ways in which the current upsurge in demands for the recognition of identities can be looked at. On the positive side, the efforts by certain population groups to assert their identity can be regarded as "liberation movements", challenging oppression and injustice. What these groups are doing - proclaiming that they are different, rediscovering the roots of their culture or strengthening group solidarity - may accordingly be seen as legitimate attempts to escape from their state of subjugation and enjoy a certain measure of dignity. On the downside, however, militant action for recognition tends to make such groups more deeply entrenched in their attitude and to make their cultural compartments even more watertight. The assertion of identity then starts turning into self-absorption and isolation, and is liable to slide into intolerance of others and towards ideas of "ethnic cleansing", xenophobia and violence.Whereas continuous variations among peoples prevent drawing of clear dividing lines between the groups, those militating for recognition of their group's identity arbitrarily choose a limited number of criteria such as religion, language, skin colour, and place of origin so that their members recognise themselves primarily in terms of the labels attached to the group whose existence is being asserted. This distinction between the group in question and other groups is established by simplifying the feature selected. Simplification also works by transforming groups into essences, abstractions endowed with the capacity to remain unchanged through time. In some cases, people actually act as though the group has remained unchanged and talk, for example, about the history of nations and communities as if these entities survived for centuries without changing, with the same ways of acting and thinking, the same desires, anxieties, and aspirations. Paradoxically, precisely because identity represents a simplifying fiction, creating uniform groups out of disparate people, that identity performs a cognitive function. It enables us to put names to ourselves and others, form some idea of who we are and who others are, and ascertain the place we occupy along with the others in the world and society. The current upsurge to assert the identity of groups can thus be partly explained by the cognitive function performed by identity. However, that said, people would not go along as they do, often in large numbers, with the propositions put to them, in spite of the sacrifices they entail, if there was not a very strong feeling of need for identity, a need to take stock of things and know "who we are", "where we come from", and "where we are going".Identity is thus a necessity in a constantly changing world, but it can also be a potent source of' violence and disruption. How can these two contradictory aspects of identity be reconciled? First, we must bear the arbitrary nature of identity categories in mind, not with a view to eliminating all forms of identification—which would be unrealistic since identity is a cognitive necessity—but simply to remind ourselves that each of us has several identities at the same time. Second, since tears of nostalgia are being shed over the past, we recognise that culture is constantly being recreated by cobbling together fresh and original elements and counter-cultures. There are in our own country a large number of syncretic cults wherein modern elements are blended with traditional values or people of different communities venerate saints or divinities of particular faiths. Such cults and movements are characterised by a continual inflow and outflow of members which prevent them from taking on a self-perpetuating existence of their own and hold out hope for the future, indeed, perhaps for the only possible future. Finally, the nation-state must respond to the identity urges of its constituent communities and to their legitimate quest for security and social justice. It must do so by inventing what the French philosopher and sociologist, Raymond Aron, called "peace through law". That would guarantee justice both to the state as a whole and its parts, and respect the claims of both reason and emotions. The problem is one of reconciling nationalist demands with the exercise of democracy.According to the author, happiness of individuals was expected to be guaranteed in the name of:
....

MCQ-> In a modern computer, electronic and magnetic storage technologies play complementary roles. Electronic memory chips are fast but volatile (their contents are lost when the computer is unplugged). Magnetic tapes and hard disks are slower, but have the advantage that they are non-volatile, so that they can be used to store software and documents even when the power is off.In laboratories around the world, however, researchers are hoping to achieve the best of both worlds. They are trying to build magnetic memory chips that could be used in place of today’s electronics. These magnetic memories would be nonvolatile; but they would also he faster, would consume less power, and would be able to stand up to hazardous environments more easily. Such chips would have obvious applications in storage cards for digital cameras and music- players; they would enable handheld and laptop computers to boot up more quickly and to operate for longer; they would allow desktop computers to run faster; they would doubtless have military and space-faring advantages too. But although the theory behind them looks solid, there are tricky practical problems and need to be overcome.Two different approaches, based on different magnetic phenomena, are being pursued. The first, being investigated by Gary Prinz and his colleagues at the Naval Research Laboratory (NRL) in Washington, D.c), exploits the fact that the electrical resistance of some materials changes in the presence of magnetic field— a phenomenon known as magneto- resistance. For some multi-layered materials this effect is particularly powerful and is, accordingly, called “giant” magneto-resistance (GMR). Since 1997, the exploitation of GMR has made cheap multi-gigabyte hard disks commonplace. The magnetic orientations of the magnetised spots on the surface of a spinning disk are detected by measuring the changes they induce in the resistance of a tiny sensor. This technique is so sensitive that it means the spots can be made smaller and packed closer together than was previously possible, thus increasing the capacity and reducing the size and cost of a disk drive. Dr. Prinz and his colleagues are now exploiting the same phenomenon on the surface of memory chips, rather spinning disks. In a conventional memory chip, each binary digit (bit) of data is represented using a capacitor-reservoir of electrical charge that is either empty or fill -to represent a zero or a one. In the NRL’s magnetic design, by contrast, each bit is stored in a magnetic element in the form of a vertical pillar of magnetisable material. A matrix of wires passing above and below the elements allows each to be magnetised, either clockwise or anti-clockwise, to represent zero or one. Another set of wires allows current to pass through any particular element. By measuring an element’s resistance you can determine its magnetic orientation, and hence whether it is storing a zero or a one. Since the elements retain their magnetic orientation even when the power is off, the result is non-volatile memory. Unlike the elements of an electronic memory, a magnetic memory’s elements are not easily disrupted by radiation. And compared with electronic memories, whose capacitors need constant topping up, magnetic memories are simpler and consume less power. The NRL researchers plan to commercialise their device through a company called Non-V olatile Electronics, which recently began work on the necessary processing and fabrication techniques. But it will be some years before the first chips roll off the production line.Most attention in the field in focused on an alternative approach based on magnetic tunnel-junctions (MTJs), which are being investigated by researchers at chipmakers such as IBM, Motorola, Siemens and Hewlett-Packard. IBM’s research team, led by Stuart Parkin, has already created a 500-element working prototype that operates at 20 times the speed of conventional memory chips and consumes 1% of the power. Each element consists of a sandwich of two layers of magnetisable material separated by a barrier of aluminium oxide just four or five atoms thick. The polarisation of lower magnetisable layer is fixed in one direction, but that of the upper layer can be set (again, by passing a current through a matrix of control wires) either to the left or to the right, to store a zero or a one. The polarisations of the two layers are then either the same or opposite directions.Although the aluminum-oxide barrier is an electrical insulator, it is so thin that electrons are able to jump across it via a quantum-mechanical effect called tunnelling. It turns out that such tunnelling is easier when the two magnetic layers are polarised in the same direction than when they are polarised in opposite directions. So, by measuring the current that flows through the sandwich, it is possible to determine the alignment of the topmost layer, and hence whether it is storing a zero or a one.To build a full-scale memory chip based on MTJs is, however, no easy matter. According to Paulo Freitas, an expert on chip manufacturing at the Technical University of Lisbon, magnetic memory elements will have to become far smaller and more reliable than current prototypes if they are to compete with electronic memory. At the same time, they will have to be sensitive enough to respond when the appropriate wires in the control matrix are switched on, but not so sensitive that they respond when a neighbouring elements is changed. Despite these difficulties, the general consensus is that MTJs are the more promising ideas. Dr. Parkin says his group evaluated the GMR approach and decided not to pursue it, despite the fact that IBM pioneered GMR in hard disks. Dr. Prinz, however, contends that his plan will eventually offer higher storage densities and lower production costs.Not content with shaking up the multi-billion-dollar market for computer memory, some researchers have even more ambitious plans for magnetic computing. In a paper published last month in Science, Russell Cowburn and Mark Well and of Cambridge University outlined research that could form the basis of a magnetic microprocessor — a chip capable of manipulating (rather than merely storing) information magnetically. In place of conducting wires, a magnetic processor would have rows of magnetic dots, each of which could be polarised in one of two directions. Individual bits of information would travel down the rows as magnetic pulses, changing the orientation of the dots as they went. Dr. Cowbum and Dr. Welland have demonstrated how a logic gate (the basic element of a microprocessor) could work in such a scheme. In their experiment, they fed a signal in at one end of the chain of dots and used a second signal to control whether it propagated along the chain.It is, admittedly, a long way from a single logic gate to a full microprocessor, but this was true also when the transistor was first invented. Dr. Cowburn, who is now searching for backers to help commercialise the technology, says he believes it will be at least ten years before the first magnetic microprocessor is constructed. But other researchers in the field agree that such a chip, is the next logical step. Dr. Prinz says that once magnetic memory is sorted out “the target is to go after the logic circuits.” Whether all-magnetic computers will ever be able to compete with other contenders that are jostling to knock electronics off its perch — such as optical, biological and quantum computing — remains to be seen. Dr. Cowburn suggests that the future lies with hybrid machines that use different technologies. But computing with magnetism evidently has an attraction all its own.In developing magnetic memory chips to replace the electronic ones, two alternative research paths are being pursued. These are approaches based on:
....

MCQ->Read the following statements and answer the question that follows:1.The periodic table orders the elements in a way that helps to understand why atoms behave as they do. 2.The properties of the elements are due to electronic configuration, and their recurring pattern gives rise to periodicity. 3.In other words, what gives the elements their properties and what order lies below the surface of their seemingly random nature? 4.What makes Fluorine react violently with Caesium while its nearest neighbour neon is reluctant to react with anything?Which of the following options is the best logical order of the above statements?....

MCQ->According to .........., the properties of elements are a periodic function of their atomic masses.....

MCQ-> When people react to their experiences with particular authorities, those authorities and the organizations or institutions that they represent often benefit if the people involved begin with high levels of commitment to the organization or institution represented by the authorities. First, in his studies of people's attitudes toward political and legal institutions, Tyler found that attitudes after an experience with the institution were strongly affected by prior attitudes. Single experiences influence post- experience loyalty but certainly do not overwhelm the relationship between pre-experience and post- experience loyalty. Thus, the best predictor of loyalty after an experience is usually loyalty before that experience. Second, people with prior loyalty to the organization or institution judge their dealings with the organization’s or institution's authorities to be fairer than do those with less prior loyalty, either because they are more fairly treated or because they interpret equivalent treatment as fairer.Although high levels of prior organizational or institutional commitment are generally beneficial to the organization or institution, under certain conditions high levels of prior commitment may actually sow the seeds of reduced commitment. When previously committed individuals feel that they were treated unfavourably or unfairly during some experience with the organization or institution, they may show an especially sharp decline in commitment. Two studies were designed to test this hypothesis, which, if confirmed, would suggest that organizational or institutional commitment has risks, as well as benefits. At least three psychological models offer predictions of how individuals’ reactions may vary as a function of a: their prior level of commitment and b: the favorability of the encounter with the organization or institution. Favorability of the encounter is determined by the outcome of the encounter and the fairness or appropriateness of the procedures used to allocate outcomes during the encounter. First, the instrumental prediction is that because people are mainly concerned with receiving desired outcomes from their encounters with organizations, changes in their level of commitment will depend primarily on the favorability of the encounter. Second, the assimilation prediction is that individuals' prior attitudes predispose them to react in a way that is consistent with their prior attitudes.The third prediction, derived from the group-value model of justice, pertains to how people with high prior commitment will react when they feel that they have been treated unfavorably or unfairly during some encounter with the organization or institution. Fair treatment by the other party symbolizes to people that they are being dealt with in a dignified and respectful way, thereby bolstering their sense of self-identity and self-worth. However, people will become quite distressed and react quite negatively if they feel that they have been treated unfairly by the other party to the relationship. The group-value model suggests that people value the information they receive that helps them to define themselves and to view themselves favorably. According to the instrumental viewpoint, people are primarily concerned with the more material or tangible resources received from the relationship. Empirical support for the group-value model has implications for a variety of important issues, including the determinants of commitment, satisfaction, organizational citizenship, and rule following. Determinants of procedural fairness include structural or interpersonal factors. For example, structural determinants refer to such things as whether decisions were made by neutral, fact-finding authorities who used legitimate decision-making criteria. The primary purpose of the study was to examine the interactive effect of individuals a: commitment to an organization or institution prior to some encounter and b: perceptions of how fairly they were treated during the encounter, on the change in their level of commitment. A basic assumption of the group-value model is that people generally value their relationships with people, groups, organizations, and institutions and therefore value fair treatment from the other party to the relationship. Specifically, highly committed members should have especially negative reactions to feeling that they were treated unfairly, more so than a: less- committed group members or b: highly committed members who felt that they were fairly treated.The prediction that people will react especially negatively when they previously felt highly committed but felt that they were treated unfairly also is consistent with the literature on psychological contracts. Rousseau suggested that, over time, the members of work organizations develop feelings of entitlement, i.e., perceived obligations that their employers have toward them. Those who are highly committed to the organization believe that they are fulfilling their contract obligations. However, if the organization acted unfairly, then highly committed individuals are likely to believe that the organization did not live up to its end of the bargain.The hypothesis mentioned in the passage tests at least one of the following ideas.
....