IntroductionThe word atom is a Greek word meaning indivisible, i.e., an ultimate particle which cannot be further subdivided. The idea that all matter ultimately consists of extremely small particles was conceived by ancient Indian and Greek philosophers. The old concept was put on firm footing by John Dalton in the form of atomic theory which he developed in the years 1803–1808. This theory was a landmark in the history of chemistry. According to this theory, atom is the smallest indivisible part of matter which takes part in chemical reactions. Atom is neither created nor destroyed. Atoms of the same element are similar in size, mass and characteristics; how
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The questions asked in mathematics in this year's AIEEE were lengthy and conceptual. The level of questions can be compared with questions asked in Mathematics section of IIT-JEE. As compared to last year, this year the questions asked in maths were difficult. Unlike like last year the numbers of questions were only 30 questions as compared to 35 questions asked in last year. This in a way is an indication that the paper or level of AIEEE is inching towards higher level of complexity, since the amount of time remains same but the number of questions asked have reduced. The total numbers of question in AIEEE 2009 were 90, with 30 in each subject. This year there
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in association with The last few weeks before the exams are most critical for students. It is during this phase that bulk of exam syllabus is revisedand reviewed for the last few times. Any short coming that becomes apparent at this stage can be easily rectified. The focusof this phase is on review, revise, recall, remember and reproduce. Whatever you learn and memorize during this periodwill be of most benefit to
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IntroductionBinomial Theoram is one chapter in which you see a question and then realise that it can easily be done in 2 or 3 ways. Definitely one of the most interesting chapters which uses concepts from calculus, trignometry, complex number prognessiong and wkhat not Binomial theoram finds use in number theory as well. So, let us prober deeper into this section.Binomial theormDefinition of Bionomial theoram If n is a +ve integer and x1 y are 2 complex number then .(x + y)n n Cr xn-r yr= nCoXn - nC1 Xn-1 y + nC2 Xn-2 y2 +............+ n Cn ynSimilarly (x - y) n = nCoXn
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Some important acids and their structural formula’s.Preparation Manufacture or industrial preparation. (1) HCOOH (Formic acid) (2) (COOH)2 Oxallic acid (3) CH3COOH (Acetic acid) (b) From pyroligneous acid (already discussed in alcohols). (c) Quick vinegar process or fermentation process In the ‘quick vinegar process’, beech shavings, contained in b
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1. Wave Motion: a) The sound waves can also be called as elastic waves and medium is needed for their propagation. Their velocity is different for different media. b) The velocity of sound waves depends on the property of inertia and coefficient of elasticity of that medium. c) In this type of motion the energy is transferred from one point to other by the propagation of disturbance in the medium. The motion of disturbance is called the wave motion. d) In simple harmonic wave the particles of the medium executes simple harmonic motion. Each particle of the medium ex
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The most special thing about this chapter is that the no. of scientists involved in developed of this concept is remarkably large. Starting with heucippus of Miletus in 440 BC it extends to 2000's. And the research is still going on. Even the great scientist EINSTEIN had his hands in developing this extraordinary concept.Atomic No.: Total no. of protons present in nucleus.Mass No.: Total no. of protons & Neutrons in neucleus.Atomic No.(Z): no. of electrons (when atom is neutral).Mass No.(A): no. of neutrons + no. of protons. Representation Ilustration: Calculate no. of protons, neutrons & electrons in . Ans: Z = 35, A = 80No. of protons
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HOW TO PREPARE CHEMISTRY AS A SUBJECT FOR IIT-JEEYou know IIT-JEE is the most prestigious & challenging examination for class XIIth students in India. It comprises of three subjects e.q. physics, chemistry & maths. Out of these physics & chemistry play a crucial role in the selection process of candidate. If you see the track record of previous years you will find that in chemistry & physics student score more marks than maths, because of the theoretical nature of these subjects Chemistry is one of the top most scoring subjects. Meticulous planning of preparation can give you a marvelous increase in your rank in IIT-JEE. Chemistry comprises of three
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OCCURRENCE OF METALSThe earth's crust is the biggest source of metals. Some soluble salts of the metals are also found in sea-water. Metals occur in nature sometimes free but mostly in combined state. The natural mode of occurrence of a metals is largely dependent on its nature. Those metals which are least reactive and have little or no affinity for oxygen, moisture and other chemical reagents occur in free or metallic or native state i.e., in uncombined state. Most of the metals are reactive and hence are found in combined state i.e., as compounds.The natural substances in which the metals or their compounds occur in the earth are called minerals. The minera
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Hydrogen bond is formed when a slightly positive hydrogen atom, attached covalently to strong electronegative atom A (e.g., F, O or N) is held by a non-bonded electron pair of another atom B. The coordination number of hydrogen becomes two and it acts as a bridging atom between A and B.Generally hydrogen bond is formed with only F, O and N atoms. Sometimes less electronegative atoms such as Cl, S etc., also take part in the formation of hydrogen bond. Hydrogen bond is denoted by dotted lines (...........). It can be defined as :The attractive force that binds a hydrogen atom, which is already covalently attached with strongly electronegative atom of gain element
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Aldehydes and ketones contains the same functional group, the carbonyl group (> C = O).Aldehydes behave as reducing agents due to presence of reducing hydrogen atom where as ketones have no such property so aldehydes easily reacts with oxidising agent. Even HCOOH shows some properties of carbonyl compounds due to presence of – CHO group. HCOOH behaves as reducing agent while in other acids no reducing hydrogen atom, so no reaction with oxidising agent. Preparation(i) Oxidation of alcohols(a) From PCC or pyredeniumchlorochromate. Which is pyridine, CrO3 and HCl, in equal ratioBy Jones reagent (CrO3 and aq. CH3COCH3) reaction goes till acids as it is a stron
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Quadratic equation is nothing but polynomial equation with degree 2.The graph of quadratic equation i.e. represents a parabola.It is often claimed that Babylonians (about 400 BC) were first to solve quadratic equation. However this is not true, Savasorda in 1145 came with complete solution of quadratic equation about 900 years from then we have many interesting things to calculate like intervals of values of x for which quadratic expression is ofone sign and many more things.So let us start solving “QUADRATIC EQUATION”INTRODUCTION:An equation of form
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Sequence and Series is one of the most important chapter that is covered in the syllabus for IIT-JEE. The summation of series is one of the most important way to reduce large series into some value and it is widely used throughout the syllabus. The tricks and techniques discussed here are very useful and are widely used in other chapters as well. The A.M- G.M inequality which will be discussed here is also a very important result that is used widely. So Let us Probe more into this Chapter... Arithmetic Progression (A.P): A sequence of numbers is said to be in A.P when difference id="_x0000_t75" coordsize="216
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Parabola is a curve of infinite extent and is not often obsened in real life as circles or shaight line are . However, the parabplaic curres are very important and have some vert good propertvies like the light raus reflected from parabolic surface passes through one foxed point. This property of parabola is luidely used in making lenses and in optics.The brridges also take parabolic shape have been centuries lod. So, now let us start studying this interesting curre in more detail.Parabola is locus of point which moves such that its distance from fixed point (focus) is always equat to its distance from fixed line (directrix) i.e. eccentricity, e
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IntroductionWe know alcohols family with their rich chemical reactivity but ethers - compounds containing a R-O- R unit are less reactive and gives relatively few chemical reactions. This lack of reactivity of ether makes them valuable as inert solvents in a number of chemical reactions.Unlike most ethers, epoxides – compounds in which the C – O – C unit forms a three-membered ring - are very reactive substances due to molecular strain.Ethers are defined as symmetrical or unsymmetrical depending on whether the two groups bonded to oxygen are the same or different. Unsymmetrical ethers are also called mixed ethers. Dimethyl ether is a symmetrical wh
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History of chemical eqm started from At beginning of 18th century whole idea of chemical eqm. is based on there basic ideas: in complete reaction, reversibility & dynamic. Berthollet, Clande Laus (1748-1822) was pioneer in this field. He tonght chemistry to Napolean & ment to Egypt in 1798. He observed these that high conc. of sod. Carbonate by Lake Neutron on edge of the desert. He conclanded that under prevailing condition, Nice in upper layee of soil hard reacted with calcium carbonate from nearby lime stone hills. From there he started on working of chemical eqm. Chemical Equilibrium
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Purely from view point chemical kinetics is as important as the IInd Law of thermodynamics Neither humans nor any other organism could exist in air if activation energy (Eact) was not an energetic barrier to second Law because all organic compounds are thermodynamically unstable in oxygen.Action of IInd law. Without chemical kinetics there would be no life of universe Air makes life impossible unless the barrier of Eact is present.Fortunately force "The IInd law of thermodynamic is time's arrow but chemical kinetics is time's variable clock." Study of speeds of the rates o
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1. The sound wave can also be called as elastic wave and medium is needed for their propagation. Their velocity is different for different media.2. The velocity of sound waves depends on the property of inertia and coefficient of elasticity of that medium.3. In this type of motion the energy is transferred from one point to other by the propagation of disturbance in the medium. The motion of disturbance is called the wave motion.4. In simple harmonic wave the particles of the medium execute simple harmonic motion. Each particles of the medium executes simple motion at all the times, though the phase o
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AIEEE 2007 Practice Test 1 - Test duration is 2 hours. Instructions 1. All questions are compulsory.2. Every question carries 3 marks.3. Do not write anything on answer sheet except in the marked area.4. Every incorrect answer carries -1(negative) mark5. The paper is of 2 hours durationSyllabusPhysics - Heat, SHM and wavesChemistry - Gaseous state Amines Mathematics - Permutation and Combination, Matrices, Binomial theorem, Exponential log series, sequence and series Q1. The temperature of a
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