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Date: 13-3-2019
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Date: 11-10-2018
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Date: 4-12-2018
1165
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The name of the 25th element comes from the Latin magnes, meaning magnet. It was discovered in 1774 by Scheele and isolated later that year by Johan Gahn. Manganese is one of the few elements that humans use on a daily basis. In 1774, a Swedish scientist named Johann Gottlieb Gahn was able to isolate manganese metal by reducing the compound of manganese dioxide. Remarkably enough, manganese has been used by humans throughout the centuries.
In pure form Manganese is a hard, brittle, gray-white metal. It is best known as an alloying agent in steel. It enhances the ability to hot-work steel and increases resistance to impact. The Roman empire used manganese in their weapons and they were able to defeat their enemies. The hardness property of manganese helped them to create strong equipment for war. Furthermore, humans have been using manganese compounds centuries before human civilization began. The history of Manganese usage traces back to the stone age era, where nomads used it as a pigment to decorate their caves and sacred places. Manganese is an element that has helped and still helps humans to improve their personal lives in various ways.
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تفوقت في الاختبار على الجميع.. فاكهة "خارقة" في عالم التغذية
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أمين عام أوبك: النفط الخام والغاز الطبيعي "هبة من الله"
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قسم شؤون المعارف ينظم دورة عن آليات عمل الفهارس الفنية للموسوعات والكتب لملاكاته
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