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Gallium is a metal that melts in your hand: its melting point, about 30°C, is just below body temperature.

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Gallium melts at 29.76°C (85.6°F), so a small piece held in a warm palm slowly turns into a silvery liquid. Brief handling is generally safe, and joke 'disappearing spoons' made of gallium melt when stirred into a hot drink, though the metal stains skin and should not be swallowed. Its discovery was a triumph for the periodic table: in 1871 Dmitri Mendeleev predicted an unknown element he called eka-aluminium, and in 1875 the French chemist Paul-Émile Lecoq de Boisbaudran found it, naming it after Gallia, the Latin name for France. Today gallium compounds, such as gallium nitride, are at the heart of LEDs and many fast phone chargers.

Türkçe oku
Galyum, avucunuzda eriyen bir metaldir: yaklaşık 30°C olan erime noktası, vücut sıcaklığının hemen altındadır.

Galyum 29,76°C'de erir; bu yüzden sıcak bir avuçta tutulan küçük bir parça yavaş yavaş gümüş renkli bir sıvıya dönüşür. Kısa süre elde tutmak genellikle zararsızdır. Galyumdan yapılan şaka amaçlı “kaybolan kaşıklar”, sıcak bir içecek karıştırılırken erir; yine de bu metal cildi lekeler ve yutulmamalıdır. Galyumun keşfi periyodik tablonun da zaferi oldu: Dmitri Mendeleyev 1871'de henüz bilinmeyen ve “eka-alüminyum” adını verdiği bir elementin varlığını öngördü; Fransız kimyager Paul-Émile Lecoq de Boisbaudran da 1875'te onu buldu ve Fransa'nın Latince adı Gallia'dan esinlenerek galyum adını verdi. Bugün galyum nitrür gibi galyum bileşikleri, LED'lerin ve birçok hızlı telefon şarj cihazının temelindedir.

Sources and further reading

Background reading: Gallium
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