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Why are the elements of group 1 is called alkali metals? |
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Answer» n :▪ General electronic configuration = ns▪ The elements of group 1 : Lithium, sodium, potassium, rubidium, caesium and francium besides hydrogen.▪ These elements are called alkali metals because they form hydroxides on reaction with water which are strongly alkaline in nature.Elements in which the last electron enters the s-orbital are called s-block elememts.▶ Physical properties :▪ Alkali metals are soft with low MELTING and boiling points due to weak metallic bonding.▪ Alkali metals have low DENSITY which INCREASES down the group from Li to Cs.▪ On exposure to moist air, all alkali metals except lithium get tarnished quickly so they are ALWAYS kept in kerosene to protect them from air.▪ All alkali metals are paramagnetic but their salts are diamagnetic in nature. |
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