العنصر الذي عدده الذري 78 هو البلاتينوم Platinum
Atomic Number: 78
Atomic Symbol: Pt
Atomic Weight: 195.09
Electron Configuration: [Xe]6s14f145d9
الخواص:
Platinum is a beautiful silvery-white metal, when pure, and is malleable and ductile. It has a coefficient of expansion almost equal to that of soda-lime-silica glass, and is therefore used to make sealed electrodes in glass systems. The metal does not oxidize in air at any temperature, but is corroded by halogens, cyanides, sulfur, and caustic alkalis.
It is insoluble in hydrochloric and nitric acid, but dissolves when they are mixed as aqua regia, forming chloroplatinic acid
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العنصر التالي عدده الذري 84
