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Date: 6-1-2019
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Date: 29-11-2018
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Date: 16-11-2018
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Physical properties of group 1 metals
General properties
The alkali metals illustrate, more clearly than any other group of elements, the influence of increase in atomic and ionic size on physical and chemical properties. Thus, the group 1 metals are often chosen to illustrate general principles. Some physical properties of the group 1 metals are given in Table 1.1.
and down group 1, differences in these energy changes almost cancel out, resulting in similar EoM+/M values. The lower reactivity of Li towards H2O is kinetic rather than thermodynamic in origin; Li is a harder and higher melting metal, is less rapidly dispersed, and reacts more slowly than its heavier congeners. In general, the chemistry of the group 1 metals is dominated by compounds containing M ions.
Considerations of lattice energies calculated using an electrostatic model provide a satisfactory understanding for the fact that ionic compounds are central to the chemistry of Na, K, Rb and Cs. That Li shows a so-called ‘anomalous’ behaviour and exhibits a diagonal relationship to Mg can be explained in terms of similar energetic considerations.
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دراسة: حفنة من الجوز يوميا تحميك من سرطان القولون
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تنشيط أول مفاعل ملح منصهر يستعمل الثوريوم في العالم.. سباق "الأرنب والسلحفاة"
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لتعزيز التواصل مع الزائرات الأجنبيات : العتبة العلويّة المقدّسة تُطلق دورة لتعليم اللغة الإنجليزية لخادمات القسم النسويّ
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