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Potassium oxide (K 2 O) is an ionic compound of potassium and oxygen.It is a base.This pale yellow solid is the simplest oxide of potassium. It is a highly reactive compound that is rarely encountered.
The calculated lattice energy gives a good estimation for the Born–Landé equation; the real value differs in most cases by less than 5%. Furthermore, one is able to determine the ionic radii (or more properly, the thermochemical radius) using the Kapustinskii equation when the lattice energy is known.
The concept of lattice energy was originally applied to the formation of compounds with structures like rocksalt and sphalerite where the ions occupy high-symmetry crystal lattice sites. In the case of NaCl, lattice energy is the energy change of the reaction Na + (g) + Cl − (g) → NaCl (s) which amounts to −786 kJ/mol. [2]
One exception is phosphorus, for which the most stable form at 1 bar is black phosphorus, but white phosphorus is chosen as the standard reference state for zero enthalpy of formation. [2] For example, the standard enthalpy of formation of carbon dioxide is the enthalpy of the following reaction under the above conditions:
A statement from the museum said four "archaeological masterpieces" were taken, including the Cotofenesti helmet, which dates from around 450 BC, and three ancient Dacian royal bracelets.
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Born–Haber cycles are used primarily as a means of calculating lattice energy (or more precisely enthalpy [note 1]), which cannot otherwise be measured directly. The lattice enthalpy is the enthalpy change involved in the formation of an ionic compound from gaseous ions (an exothermic process ), or sometimes defined as the energy to break the ...