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原子核的衰变、半衰期

> 23892 U经过核衰变成为 22286 Rn，共发生了______次α衰变，______次β衰变． 21083 Bi的半衰期是5天，12g的 21083 Bi经过15天后剩下______g．

问题：

发布时间：2024-09-09

23892

U经过核衰变成为

22286

Rn，共发生了次α衰变，次β衰变．

21083

Bi的半衰期是5天，12g的

21083

Bi经过15天后剩下__g．

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