GA
Gallium (symbol Ga, atomic number 31) is a chemical element in group 13 of the periodic table. It is a soft, silvery-blue metal with a very low melting point of 29.76 °C, so it can melt in a warm hand. At room temperature it remains solid but becomes malleable as it approaches its melting point. It expands slightly upon solidification and has a high boiling point of about 2,204 °C. It forms a thin protective oxide layer when exposed to air.
Occurrence and production: Gallium is not found free in nature and occurs only in trace amounts in
Isotopes and history: Naturally occurring gallium consists of two stable isotopes, 69Ga and 71Ga. In 1875, French
Applications: Gallium is essential in electronics and optoelectronics. Gallium arsenide (GaAs) and gallium nitride (GaN) are
Safety: Gallium metal is considered of low toxicity; certain gallium compounds can be hazardous and should