Salting the Earth Group 1 Elements

Group 1 includes common elements such as sodium as well as elements that are much more rare (such as francium). The Group 1 elements display the least amount of variation in properties of the compounds they form. Found on the far left side column of the periodic table, all these elements have one electron in the outer orbital that they quite readily give up. This makes these elements much too reactive for them to exist freely in nature. They are highly reactive, combining readily with many other elements. 

They most commonly form ionic compounds (see Chapter 8 for details on ionic bonding), or salts. This is a result of their tendency to form positively charged ions, or monovalent M+ cations. (The exception to this is lithium at the top of the period, or column. With its small size, it has a partial covalent character in many compounds, similar to magnesium in Group 2.) They are called the alkali metals because their hydroxides are alkaline, or basic, and many of their salts dissolve into water to form alkaline solutions. 

All of the metals are very strong reducing agents (Chapter 3 covers reduction reactions). A reducing agent works by giving an electron to another atom. 

If you rank all metals by their reduction potential, lithium is the lowest and therefore the strongest reducing metal. 

The salts of these elements are very soluble in water, due to the low lattice energies and the high hydration energy of the atoms. They all react explosively with water lithium has the slowest reactivity, and francium the fastest. Cesium is the most electropositive stable element (because francium is unstable), and it s even known to react with ice at temperatures as low as -116 °C (-177 °F). 

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