الرئيسية » أرشيف الوسم : energy

أرشيف الوسم : energy

Electron affinity

Electron affinity It is the amount of energy given out when an electron is added to a neutral gaseous atom. This results in the formation of an anion. For example Cl + e– → Cl + energy. The electron affinity of chlorine is 348 kJ mol-1. Electron affinity changes across …

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Ionization energy

Ionization energy (or potential) of an element is defined as “The amount of energy required or needed to remove an electron from the neutral gaseous atom to form unipositive ion , for example Na → Na+ + e– + energy This is measured in electron volts per atom or kJ …

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Quantization

Quantization: means that a quantity does not vary continuously. The energy of an electron in an atom cannot have any arbitrary value but only certain characteristic values. ­A definite quantum of energy is accepted while moving from lower to higher energy level or lost while moving from higher to lower …

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adiabatic demagnetization

A technique for cooling a paramagnetic salt, such as potassium chrome alum, to a temperature near absolute zero. The salt is placed between the poles of an electromagnet and the heat produced during magnetization is re­moved by liquid helium. The salt is then isolated thermally from the sur­roundings and the …

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Atomic Theory

Dalton’s Model of the atom. It is the basis of our understanding of the nature of matter. The following four statements comprise Dalton’s Model: a –  All matter is made up of extremely tiny. particles. called atoms. b-  Atoms are indivisible. c – Atoms of the same element are alike. …

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Energy

Like matter, energy can be classified in different ways. For example, energy can either be kinetic or potential. Kinetic energy is energy of motion. Gases are made of molecules that have more kinetic energy than molecules in the solid phase of that substance. For example, water molecules in steam have …

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