Gallium

Gallium (chemical symbol: Ga) is element 31 on the periodic table. It is a soft, gray metal that is rare on Earth. It can easily be melted just by holding it in your hand, as its melting point is very low 29.76 Celsius (85.58 Fahrenheit), however it also sticks to your hand a lot, unlike mercury. Gallium is a semiconductor, and as the compound Gallium arsenide it is used in electronics and LEDs. Then, Gallium is also used in mirrors. Gallium can also be alloyed with indium and tin to create galinstan. Gallium is similar to the elements aluminium, indium, and mercury. Gallium is also used to make alloys that are liquid at room temperature. These can be used as a thermal paste for computers, and as a substitute for mercury in some applications.

Gallium's existence was predicted by Dmitri Mendeleev in 1871. Four years later, it was discovered by Paul-Émile Lecoq de Boisbaudran.

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Category:Post-transition metals