A complete A-Z dictionary of chemistry terms.
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Definition Hydrogen bonding is a weak type of force which forms a dipole-dipole interaction between two molecules within the same molecule. Depending upon different contexts, its definition has been changing. According to earlier definitions “Hydrogen bonds is an interaction between the covalent pair A—H (donor) to a nearby electronegative atom B or X (acceptor). And … Read more
Introduction What is a chemical bond? A Chemical bond detains molecules together. It also creates temporary connections that are essential to life. What is chemical bonding? Chemical bonding is any relationship that is responsible for the association of atoms into molecules, ions, crystals and other species that makes up the substance of the everyday world. … Read more
Definition According to Dalton’s theory atom is smallest particle which could not be divided any further. Atom is the entity that take part in a chemical reaction. For example, He and Ne, etc. have atoms, which exists independently. While atoms of hydrogen, nitrogen and oxygen do not exist independently. An atom is further composed of … Read more
History Initially, the term covalence concerning bonding was used in 1919, by Irving Langmuir in an American journal known as the Journal of the American Chemical Society under the title of “The Arrangement of Electrons in Atoms and Molecules.” Langmuir wrote in his journal that “we shall denote by the term covalence the number of … Read more
Definition The ionization energy of an element is the minimum energy required to remove an electron from the valence shell of an isolated gaseous atom to form an ion [1]. For example: Mg → Mg + e– ΔH = 738kjmol-1 Explanation In the gaseous phase, the atoms and ions are isolated and are free from … Read more
Introduction The van der Waals force was named after a Dutch scientist Johannes Diderik van der Waals (1837-1923). This is considered as the first type of intermolecular forces between atom and molecules. Like ionic or covalent bonds, these attraction forces do not result from a chemical bond as they are comparatively weak and hence can … Read more
Introduction of Ionic Bond Ionic bond is a kind of chemical bond which involves an electrostatic attraction between two oppositely charged ions because of the complete transfer of valence electrons between them. As for example: metals such as sodium losses electrons to to become positive ion, whereas non-metal such as chlorine accepts electrons to become … Read more
Atomic Orbitals Definition Orbit is the definite path of an electron that moves around the nucleus in an atom. This is similar to a planet, moves around the sun. Orbitals are the space or region around the nucleus where the electron are calculated to be present. So orbits and orbitals have totally different meanings. Shapes … Read more