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Physical Chemistry

Valence Bond Theory

Science > Chemistry > Physical Chemistry > Nature of Chemical Bond > Valence Bond Theory Valence bond theory was proposed by Heitler and London in (1927) and it was extended by Pauling and Slater (1931). It is based on the following concepts. The pairing of electrons. Neutralization of opposite electron spins. Overlapping of orbitals containing […]

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Physical Chemistry

Formation of Covalent Bonds

Science > Chemistry > Physical Chemistry > Nature of Chemical Bond > Formation of Covalent Bonds In previous articles, we have seen formation of ionic bonds. In this article, we shall study the concept of the formation of a covalent bond. Covalent Bonds or Electron Pair Bonds: A bond established between two identical or different atoms […]

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Physical Chemistry

Properties of Ionic Compounds

Science > Chemistry > Physical Chemistry > Nature of Chemical Bond > Properties of Ionic Compounds In this article, we shall study the properties of ionic compounds. Physical State: Due to strong electrostatic force present between the oppositely charged ions, they are held closer and fixed at specified positions in the crystal lattice. Hence ionic […]

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Physical Chemistry

Factors Governing Formation of Ionic Bond

Science > Chemistry > Physical Chemistry > Nature of Chemical Bond > Factors Governing Formation of Ionic Bond In this article, we shall study the factors affecting the formation of the ionic bond and the concept of variable electrovalency. Ionization energy of Electropositive Atom: It is defined as the amount of energy required to remove the […]

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Physics

Conservation of Energy

Science > Physics > Work, Power, and Energy > Conservation of Energy In this article, we shall study the concept of energy, types of mechanical energies, and the law of conservation of energy Energy: Different types of energy are mechanical energy, sound energy, heat energy, light energy, chemical energy, electrical energy, atomic energy, nuclear energy. […]

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Physics

Work and Power

Science > Physics > Work, Power, and Energy > Work and Power In this article, we shall study the concept of work and power. Work: When a force is applied to a body and there is the displacement of the body in the direction of the force or along the direction of the component of […]

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Physics

Thermodynamics

Science > Physics > Themodynamics > Laws of Thermodynamics In this article, we shall study the laws of thermodynamics and the concept of work done in a process. Zeroth Law of Thermodynamics: If two bodies P and Q are in thermal equilibrium and also P and R in thermal equilibrium then Q and R, are […]

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Physics

Natural Radioactivity

Science > Physics > Nuclear Physics > Natural Radioactivity Radioactivity was discovered by French physicist Antoine Becquerel in 1896. He found that certain compounds of uranium emitted invisible radiations which affected photographic plates. It is also found that Thorium and its compounds also show these properties. Madame Curie and Piere Curie discovered two elements namely […]

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Physics

Introduction to Reflection of Light

Science > Physics > Optics > Reflection of Light > Introduction to Reflection of Light When a ray of light approaches a smooth polished surface and the light ray bounces back, it is called the reflection of light. The surface which reflects the light is called a reflecting surface. The ray of light approaching the […]

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Physical Chemistry

Octet Theory

Science > Chemistry > Physical Chemistry > Nature of Chemical Bond > Octet Theory The force of attraction which keeps atoms or ions together in a molecule is called a Chemical bond. The main cause of chemical combination is the tendency to acquire stability i.e. a state with minimum energy and a tendency to acquire […]