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Present a comparative account of the alkali and alkaline earth metals with respect to the following characteristics : (a) Tendency to form ionic/covalent compounds.(b) Nature of oxides and their solubility in water. (C) Formation of oxosalts (d) Solubility of oxosalts (e) Thermal stability of oxosalts |
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Answer» Solution : (a) ALKALINE EARTH metals give ionic compounds but these compounds are less ionic than alkali metals because of more effective nuclear CHARGE and small size. (b) Oxides of alkaline earth metals are less basic than the oxides of alkali metals. These oxides are WATER soluble and the reactions are highly exothermic. Hydroxides of alkaline earth metals are less basic than hydroxides of alkali metals. (c) Alkaline earth metals give oxo salts with oxoacids but reactivity of alkali metals is faster. The reactivity of alkaline earth metals is less due to small size and more nuclear charge. (d) Oxosalts of alkaline earth metals are more soluble than oxosalts of alkali metals because of small size of cation and high hydration enthalpy. (e) Thermal stability of oxosalts of alkali metals is more than oxosalts of alkaline earth metals. `Na_(2)CO_(3)`is stable towards heat but `MgCO_(3)` on heating is decomposed into MgO and `CO_(2)`. |
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