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tu18052003
2 năm trước
: Nguyên tử của nguyên tố X có tổng số hạt proton, nơtron và electron là 28, trong đó tổng số hạt mang điện hơn số hạt không mang điện là 8 hạt. (a) Tính số proton, nơtron và electron của X. (b) Xác định số khối và viết kí hiệu nguyên tử của X. (c) Viết cấu hình electron của X
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