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GA - 4 reference results
Ga, black African ethnic group, SE Ghana. The Ga speak a Kwa language and, together with the closely related Adangme, number over 1 million. Inheritance and succession to public office are determined mostly by patrilineal descent. According to their oral traditions, the Ga came from the region of Lake Chad and migrated into present-day Ghana beginning in the 16th cent. They established Great Accra (near modern Accra) as their capital. The Ga were on friendly terms with Danish traders in the mid-17th cent. Between 1677 and 1681 they were conquered by the Akwamu state, and in 1742 the Ashanti gained control over them. In 1874 the Ga were incorporated into the British Gold Coast colony.
Ga, symbol for the element gallium.

Metallic chemical element, chemical symbol Ga, atomic number 31. Silvery white and soft enough to be cut with a knife, gallium has an unusually low melting point (about 30 °C [86 °F]), which allows it to liquefy in the palm of the hand. The liquid metal clings to or wets glass and similar surfaces. Gallium expands on solidification and supercools readily, remaining liquid at temperatures as low as 0 °C (32 °F). In various combinations with aluminum, indium, phosphorus, arsenic, and antimony, it forms compounds (e.g., gallium arsenide and indium gallium arsenide phosphide) with valuable semiconductor and optoelectronic properties; some of these compounds form the basis for such electronic devices as light-emitting diodes and semiconductor lasers.

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