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giang2009
2 năm trước
Trong tự nhiên nguyên tố Mg có 3 đồng vị .Trong đó đồng vị 24 Mg (78,6%) và 26 Mg (11,3%) .Tìm số khối của đồng vị còn lại biết rằng khối lượng của 20 nguyên tử Mg là 486,54u?
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