وفّر 50٪ من خلال الاشتراك السنوي في مجرة واحصل على تصفح لا محدود لأفضل محتوى عربي على الإنترنت.
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هو معدن لامع أبيض مُرزق، يتصف بالليونة والمرونة العالية، ويعد موصلاً ضعيفاً نسبياً للكهرباء، ويتمتع بمقاومة شديدة للتآكل ولكنه يتأكسد عند التعرض للهواء.
يتميز الرصاص بالمواصفات التالية:
يُستخدم الرصاص على نطاق واسع في الصناعات التالية:
تشمل خصائص الرصاص الفيزيائية ما يلي:
يعتبر القدماء المصريون أول من استخرج الرصاص؛ حيث استخدموه في صنع المنحوتات الصغيرة، وتم استخدام الرصاص لتزوير العملات في نحو عام 2000 قبل الميلاد بالصين.
يتم الحصول على الكثير من خام الرصاص كمنتج ثانوي لتعدين المعادن الأخرى مثل الزنك أو الفضة، حيث يُستمد نصف الرصاص المستخدم سنوياً من التعدين، ونصفه الآخر من خلال إعادة تدوير بطاريات السيارات.
لا يشكل الرصاص سوى نحو 0.0013% من قشرة الأرض، إلا أنه لا يعتبر عنصراً نادراً إذ يسهل تعدينه وتنقيته.
يعتبر الرصاص ضاراً بالبشر بشكل كبير؛ لأنه يتداخل مع العديد من الإنزيمات الموجودة داخل خلايا الجسم، ينتج عن التسمم بالرصاص أعراض مثل آلام العضلات والمفاصل وكذلك الإمساك والتعب العام، ويؤثر الرصاص بشكل سلبي جداً على الدماغ وعلى آليات النقل العصبي.
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