Wikipedia:Good topics/Alkali metals
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The alkali metals (lithium, sodium, potassium, rubidium, caesium, and francium) are the most homogeneous column of elements in the periodic table, exhibiting very clear periodic trends. All of them are soft and extremely reactive metals, readily giving up their sole valence electron to form cations. Their history spans over centuries, from the ancient use of sodium and potassium salts to the ongoing attempts to make the elusive element 119. All five stable alkali metals have important applications, with sodium and potassium being essential elements for life.