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Zerabao
2 năm trước
Nguyên tố Cu có nguyên tử khối trung bình là 63,54 có 2 đồng vị X và Y, biết tổng số khối là 128. Số ng tử đồng vị X = 0,37 số nguyên tử đồng vị Y. Vậy số khối của X và Y lần lượt là? X là kim loại hóa trị II, Y là kim loại hóa trị III. Tổng số hạt trong nguyên tử X là 36 và trong nguyên tử Y là 40. X, Y là
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