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Date: 5-5-2019
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Date: 4-1-2017
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Date: 19-12-2015
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Aqua species of beryllium
We have already noted that there is a high tendency to form [Be(H2O)4]2+ in aqueous media. In 17O-enriched water, exchange between coordinated water and solvent is slow on the NMR spectroscopic timescale, permitting the nature of the hydrated ion to be established. The tetrahedral coordination sphere (Be-O = 162.0 pm) has been established in the solid state structure of [Be(H2O)4][O2CC≡CCO2] (Figure 1.1). The charge density of Be2+ is high and solutions of beryllium salts are acidic. Reaction showen in below is an over-simplistic representation of the dissociation, since various condensation processes occur and hydroxo-bridged species are also present.
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دراسة: عدم ترتيب الغرفة قد يدل على مشاكل نفسية
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علماء: تغير المناخ تسبب في ارتفاع الحرارة خلال موسم الحج
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عمره عام واحد ويعاني من ورم خبيث بوزن (3) كغم وعلى نفقة العتبة الحسينية ... مستشفى خديجة الكبرى (ع) ينجح باستئصال ورم سرطان الكلى لطفل من محافظة الأنبار
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