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First Ionization Energy

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

Atomic Orbitals

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

Atomic radius

Definition of atomic radius The atomic radius is the size of the atom, typically measured by the distance from the nucleus of the atom to the electron clouds around the nucleus. As there are no physical existence of orbital in atoms, it is difficult to measure the atomic radius. Thus sometime different methods are used … Read more

Electron affinity

Definition of electron affinity Electron affinity is the affinity of an element to an electron. This is measured by the energy released when an element in its gaseous state accepts an electron to form an anion. So this is an exothermic reaction. They are expressed in KJ mol-1. M(g) + e– → M–(g)       EA Since … Read more

Ionization Energy

Ionization Energy Definition The ionization energy (IE) or ionization potential is the energy needed to remove an electron from an atom in the gaseous state. M(g) → M+(g) + e–      IE Since one, two or more electrons can be removed from an atom, many ionization energy is possible of that atom. The first ionization energy (IE1) … Read more