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Carbon is tetravalent, so it cannot have six covalent bonds attached with it. The given structure is wrong.
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P1 V1 / T1 = P2 V2 / T2 20 * 2.82 / 300 = 1 * V2 / 273 V2 = Volume of gas at STP = 51.32 l Volume of gas filled in the balloons = 51.32 - 2.82 = 48.50 l (because gsa equal to the vol of cylinder would still remain in the cylinder as we cannot expect a vaccum). Now divide this volume with the volume of sphere (4/3  r 3 ). You will get the number of balloons filled. |
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Arun sir is right. Hastily read 'a compound' instead of 'an organic compound'.
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Sodium hydride would give hydrogen at anode and cathode.
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In chemistry, activation energy, also called threshold energy, is a term introduced in 1889 by Svante Arrhenius that is defined as the energy that must be overcome in order for a chemical reaction to occur. Activation energy may otherwise be denoted as the minimum energy necessary for a specific chemical reaction to occur. The activation energy of a reaction is usually denoted by Ea, and given in units of kilo joules per mole. Basically, the activation energy is the height of the potential barrier (sometimes called the energy barrier) separating two minima of potential energy (of the reactants and of the products of reaction). For chemical reaction to have noticeable rate, there should be noticeable number of molecules with the energy equal or greater than the activation energy. There are three necessary requirements in order for a reaction to take place: - 1. the molecules must collide to react.
If two molecules simply collide, however, they will not always react; therefore, the occurrence of a collision is not enough. The second requirement is that: - 2. there must be enough energy (energy of activation) for the two molecules to react.
This is the idea of a transition state; if two slow molecules collide, they might bounce off one another because they do not contain enough energy to reach the energy of activation and overcome the transition state (the highest energy point). Lastly, the third requirement is: - 3. the molecules must be orientated with respect to each other correctly.
For the reaction to occur between two colliding molecules, they must collide in the correct orientation, and possess a certain, minimum, amount of energy. As the molecules approach each other, their electron clouds repel each other. Overcoming this repulsion requires energy (activation energy), which is typically provided by the heat of the system; i.e., the translational, vibrational, and rotational energy of each molecule, although sometimes by light ( photochemistry) or electrical fields ( electrochemistry). If there is enough energy available, the repulsion is overcome and the molecules get close enough for attractions between the molecules to cause a rearrangement of bonds. At low temperatures for a particular reaction, most (but not all) molecules will not have enough energy to react. However there will nearly always be a certain number with enough energy at any temperature because temperature is a measure of the average energy of the system ? individual molecules can have more or less energy than the average. Increasing the temperature increases the proportion of molecules with more energy than the activation energy, and consequently the rate of reaction increases. Typically the activation energy is given as the energy in kilojoules needed for one mole of reactants to react |
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Pilani is older if not better of Birla Institutes. I think Chem Pilani would be a right choice.
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Apart from Morrison Boyd, P.L Soni is a good book. J.D Lee is an excellent book for reference in Inorganic.
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Water has a maximum density at 4 degrees.
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According to Rutherford, an electron revolves around the nucleus in cirular paths. But according to classical theory, any particle in acceleration loses energy constantly. If this be so, then an electron revoving around the nucleus will lose energy whereby its orbit will become smaller and smaller and it will finally fall in the nucleus. But this does not happen. Rutherford also failed to explain the spectral lines observed in the Hydrogen spectrum. To overcome these shortcomoings, Neil Bohr put forward his postulates based on the Quantum theory of radiation. Bohr stated that electrons revolve around the nucleus in fixed orbits with definite energies and at a fixed distance from the nucleus. During its motion, the electron does not gain or lose energy.Only when an electron is supplied energy, that it jumps to a higher energy level or orbit. Similarly if it transits to a lower energy, then it loses energy. The energy gained or lost is equal to one quanta, h  where h is the planck's constant and is the frequency of radiation. Bohr also explained the line spectra observed in the Hydrogen spectrum. |
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There seems to be some error in the question. However you can proceed like this. From the first part of the question you can find Kp from the given values of degree of dissociation and total pressure after calculating the number of moles of each component namely ammonia, nitrogen and hydrogen. Individual moles/total moles * total pressure will give partial pressure of each component.So you can calculate Kp for the dissociation of ammonia. Now , in the second part, you are given initial concentrations and equilibrium concentration, but equilibrium conc. is numerically wrong because 425 gm comes to be more than the total weights of different components as calculated from the given number of moles in the mixture.So check this value again. Then find out equilibrium conc. of ammonia, nitrogen and hydrogen. (Neon will not interfere in the reaction, it will only be used in calculating the total pressure). Put in the same equation of Kp which is already calculated. Total pressure will come.
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There seems to be some error in the question. However you can proceed like this. From the first part of the question you can find Kp from the given values of degree of dissociation and total pressure after calculating the number of moles of each component namely ammonia, nitrogen and hydrogen. Individual moles/total moles * total pressure will give partial pressure of each component.So you can calculate Kp for the dissociation of ammonia. Now , in the second part, you are given initial concentrations and equilibrium concentration, but equilibrium conc. is numerically wrong because 425 gm comes to be more than the total weights of different components as calculated from the given number of moles in the mixture.So check this value again. Then find out equilibrium conc. of ammonia, nitrogen and hydrogen. (Neon will not interfere in the reaction, it will only be used in calculating the total pressure). Put in the same equation of Kp which is already calculated. Total pressure will come.
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Find separate tutors for different subjects if you are not satisfied with this particular tutorial. When you prepare for Engineering entrance, then the board preparation automatically gets covered.Do not avoid school, just put in the extra labour.
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You might get BITS in Dubai. Only thing is the expenditure. If its okay with you, then you can go ahead.
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The concept of an electron following a definite orbit where its position and velocity cannot be known exactly and that there is only a probability of finding an electron in a particular position or in a particular volume of space is well explained by the Schrodinger wave equation.According to this equation, where  is delta used for three partial differentials of x, y, and z dimensions  is the wave function m is the mass of the electron h is the Planck's constant E is kinetic energy plus the potential energy V Acceptable solutions to the wave equation, that is solutions which are physically possible, must have certain properties : 1. must be continuous 2. must be finite 3 must be single valued 4.The probability of finding the electron over all the space from plus infinity to minus infinity must be equal to one. The probability of finding an electron at a point x, y, z is 2So, Several wave functions called 1, 2, 3 ..... will satisfy these conditions to the wave equation, and each of them has a corresponding energy E 1 , E 2, E 3 ....Each of these wave functions 1, 2 is called an 'orbital'. |
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You are in need of getting encouraged.Go ahead with your preparations, you shall succeed. But first of all stop worrying !
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Carbon tetrachloride vapours react with steam at 5000 C to give phosgene. CCl 4 + H 2O  Cl-C-Cl + 2HCl II O Phosgene
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de Broglie put forth the idea that if light waves can have particle like behaviour,then particles of matter can perhaps show characteristics of wave. The two fundamental equations obeyed by photons are, E = h  and E = mc Combining the two relations, E = mc 2 = h = mc 2 /h c/ = h/mc ie.,  = h/mc where is the wavelength m is the mass of the particle h is the Planck's constant c is the velocity of light de Broglie postulated that a particle of mass m moving with a velocity v has an associated wavelength . de Broglie relation is = h/mv mv is called the momentum p of the particle, so that = h/p
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If you are not interested in Biotech, then the second best choice is BITS Pilani.
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XI th Standard is the foundation year for the preparation of JEE. Study each chapter in each subject very closely from the text books. Do not start solving guides as early as now. Strengthen the basics and concepts first.In addition to classroom study, go a little deeper.Join some good coaching also, but not more than two subjects at a time.Give more number of hours to studies.
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(b) Plot of log p vs 1/T will be a straight line with a negative slope.
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