Type of nr: alpha 235 u —> + 231 th 92 90

Type of NR: alpha 235 U —> + 231 Th 92 ___ 90

²³⁵92U → ⁴2He(2p,2n) + ²³¹90Th.

²³⁵92U → Helium nucleus + ²³¹90Th.

Explanation : This is typical Alpha decay, as an alpha is a Helium Nucleus. The Alpha decay of Uranium-235 changes both the mass number and the atomic number of the element from 235 to 231 and from 92 to 90. The mass number decreases by 4, and the atomic number decreases by 2. This gives rise to the formation of a new element - Thorium-231.

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