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Date: 1-1-2018
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Date: 28-12-2018
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Chromium
Chromium is the 24th element in the periodic table and it is found in about 0.0122% of the Earth's crust. It is named after the Greek word "chroma," meaning color. This element produces many beautifully colored compounds, as well as a wide array of colored solutions. Chromium is also a very useful industrial metal.
Discovered in 1797 by Louis-Nicholas Vauquelin and isolated a year later, chromium is a very hard steel-gray metal which takes its name from the Greek word chroma, for "color", suggesting the wide variety of colors which characterize its compounds, many of which are used as oil paint pigments. the pure metal is also a valuable alloying agent for spring steels and along with nickel, in stainless steels. Chromium(III) oxide (a popular green pigment) is the ninth most abundant chemical in the earth's crust.
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"عادة ليلية" قد تكون المفتاح للوقاية من الخرف
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ممتص الصدمات: طريقة عمله وأهميته وأبرز علامات تلفه
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المجمع العلمي للقرآن الكريم يقيم جلسة حوارية لطلبة جامعة الكوفة
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