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Hello Students, Do you know ---- Q: Why are the atomic orbitals of oxygen atom in the molecular orbital diagram of carbon monoxide, CO, lower than those of carbon? A: It is because the electronegativity of oxygen is larger than that of carbon. Q: Which halogen has the largest oxidizing power? A: Since the reduction potential of fluorine is the highest, its oxidizing power is the largest. Q: Describe the numerical tendency of electronegativities of the elements in the periodic table. A: They increase toward the right and decrease down the table. Namely, the electronegativity of alkali metal Cs is the smallest and that of fluorine F is the largest. # eCLASS   # PhysicsConcepts   # ChemistryConcepts   # ScienceConcepts   # CBSEScience   # ICSEScience   # NIOSClasses

Hello Stude nts, Do you know about the "Hydrogen Bonding" !!!! The very large difference in electronegativity between the H atom and the atom to which it is bonded combined with the very small size of a H atom and the relatively small sizes of F, O, or N atoms, leads to highly concentrated partial charges with these atoms. Molecules with F-H, O-H, or N-H moieties are very strongly attracted to similar moieties in nearby molecules, a particularly strong type of dipole-dipole attraction called hydrogen bonding. Examples of hydrogen bonds include HF…HF, H2O…HOH, and H3N…HNH2, in which the hydrogen bonds are denoted by dots. Hydrogen bonds are much weaker than covalent bonds, only about 5 to 10% as strong, but are generally much stronger than other dipole-dipole attractions and dispersion forces. For example : consider the trends in boiling points for the binary hydrides of group 15 (NH3, PH3, AsH3, and SbH3), group 16 hydrides (H2O, H2S, H2Se, and H2Te), and group 1...

  Principle of Physics     Electromagnetic Induction Laws of Thermodynamics Electromagnetic Waves propagation Nuclear chain reaction Newtons Second & Third Law Bernoulli’s theorem Population inversion X-rays Electromagnetic Induction Technology   Electricity Generation Steam, petrol, or diesel Engine Radio, TV, Phones Nuclear reactor for power Rocket propulsion Aero planes Lasers Medical Diagnosis Electricity Generation                                          If you wa n t to joi n us, you ca n like our page a n d share to your frie n ds. We will update Facts, Su bjects topics, Q & A Sessions, Classroom videos on this page. & yes of course.. Stay Safe... Stay Healthy... and Stay Connected to us.

Do you k now a bout the Quantum Theory of Electrons in Atoms !!!! See,  The energy levels are labeled with an n value, where n = 1, 2, 3,…  So, generally speaking, the energy of an electron in atom is greater for greater values of n . This number, n , is referred to as the principle quantum number.   The principle quantum number defines the location of the energy level. It is essentially the same concept as the n in the Bohr atom description. Another name for the principal quantum number is the shell number. The shells of an atom can be thought of concentric circles radiating out from the nucleus. The electrons that belong to a specific shell are most likely to be found within the corresponding circular area. The further we proceed from the nucleus, the higher the shell number, and so the higher the energy level. The positively charged protons in the nucleus stabilize the electronic orbitals by electrostatic attraction between the positive charges of the protons a...

The kinetic theory of gases explains the  macroscopic  properties of gases like volume, pressure, and temperature, as well as  transport properties  such as  viscosity ,  thermal conductivity  and  mass diffusivity .   The theory for ideal gases makes assumptions like --- ·         The gas consists of very small particles known as molecules. This smallness of their size is such that the total  volume  of the individual gas molecules added up is negligible compared to the volume of the smallest open ball containing all the molecules. This is equivalent to stating that the average distance separating the gas particles is large compared to their  size .                            ·         These particles have the same  mass . ·         The ...

Do you k now a bout the Valence Bond Theory !!! Actully this theory describes a covalent bond as the overlap of half-filled atomic orbitals (each containing a single electron) that yield a pair of electrons shared between the two bonded atoms. We say that orbitals on two different atoms overlap when a portion of one orbital and a portion of a second orbital occupy the same region of space.   According to valence bond theory, a covalent bond results when two conditions are met: (1) an orbital on one atom overlaps an orbital on a second atom   (2) the single electrons in each orbital combine to form an electron pair.   The mutual attraction between this negatively charged electron pair and the two atoms’ positively charged nuclei serves to physically link the two atoms through a force we define as a covalent bond. The strength of a covalent bond depends on the extent of overlap of the orbitals involved. Orbitals that overlap extensively form bonds that are st...

Do you k now a bout the calorimetry !!!   One technique we can use to measure the amount of heat involved in a chemical or physical process is known as calorimetry .   Calorimetry is basically used to measure amounts of heat transferred to or from a substance. To do so, the heat is exchanged with a Calorimeter. The change in temperature of the measuring part of the calorimeter is converted into the amount of heat.                           A calorimeter is a device used to measure the amount of heat involved in a chemical or physical process. For example, when an exothermic reaction occurs in solution in a calorimeter, the heat produced by the reaction is absorbed by the solution, which increases its temperature. When an endothermic reaction occurs, the heat required is absorbed from the thermal energy of the solution, which decreases its temperature.   If you wa n t to joi n us, you ca n ...

Do you k now !!!   The word Science originates from the Latin verb Scientia meaning ‘ to know ’ . Science, in a broad sense, is as old as human species. The early civilisations of Egypt, India, China, Greece, Mesopotamia and many others made vital contributions to its progress. From the sixteenth century onwards, great strides were made in science in Europe. By the middle of the twentieth century, science had become a truly international enterprise, with many cultures and countries contributing to its rapid growth.   We will update Facts, Su bjects topics, Q & A Sessions, Classroom videos on this page.  Like and Share this page to more and more friends & students. & yes of course Stay Safe... Stay Healthy... Stay Connected.