Isotopes are atoms that have the same number of protons and electrons but different numbers of neutrons and therefore have different physical properties.
例句
...tritium, a radioactive isotope of hydrogen.氢的放射性同位素氚
英汉词典释义
n.
<核>同位素
Tritium is one of the mildest radioactive isotopes.氚是最和缓的放射性同位素之一。
英英词典释义
Noun
1. one of two or more atoms with the same atomic number but with different numbers of neutrons