Final answer:
When an original isotope undergoes a nuclear decay reaction, a new element is formed as a different isotope with different chemical properties.
Step-by-step explanation:
When an original isotope undergoes a nuclear decay reaction, a new element is formed. This new element is referred to as a different isotope, which has a different number of protons and neutrons in its nucleus compared to the original isotope. The change in the number of protons results in the formation of a new element with different chemical properties.
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