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Date: 25-7-2020
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Chemical bond
chemical bond is the force that holds atoms together in a chemical compound. There are three idealized types of bonding: covalent bondingA type of chemical bonding in which electrons are shared between atoms in a molecule or polyatomic ion., in which electrons are shared between atoms in a molecule or polyatomic ion, ionic bondingA type of chemical bonding in which positively and negatively charged ions are held together by electrostatic forces., in which positively and negatively charged ions are held together by electrostatic forces and metallic bonding, where all of the atoms in the metal share a few of their electrons which are free to circulate. One can relate the properties of materials to the type of bonding. Ionic compounds, for example, typically dissolve in water to form aqueous solutions that conduct electricity as the ions separate into solution. Solid ionic compounds do not conduct eletricity or heat. In contrast, most covalent compounds that dissolve in water form solutions that do not conduct electricity because they go into the solvent as neutral molecules. The solids or liquids are not conductors. In metals, of course, the free electrons conduct electricity, and what is not obvious, also heat. Metals are good conductors of both. Further, in general, covalent compounds are volatile because the forces holding the neutral molecules together are relatively weak, whereas ionic compounds are not because the individual ions are strongly attracted to each other.
Despite the differences in the distribution of electrons between these idealized types of bonding, all models of chemical bonding have three features in common:
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منها اللوز.. أطعمة تساعدك على النوم بشكل أفضل
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علماء: وشاح الأرض قد يحتوي على ثروة من "المعادن الخضراء"
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بالصور: صرح تربوي جديد تضيفه العتبة الحسينية.. شاهد كيف أصبح مجمع مدارس الوارث في حي السلام
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مركز ميزان للرعاية الصحية التابع للعتبة الحسينية المقدسة يحصي خدماته المقدمة ضمن مبادرة عطاء المجتبى (ع) الطبية مدفوعة التكلفة
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بالفيديو: في مستشفى المجتبى (ع) لإمراض الدم وزراعة نخاع العظم.. مراجعون يقدمون شكرهم لممثل المرجعية العليا والعتبة الحسينية على المبادرات التي تخدم العراقيين
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