Question 3 of 15 A reaction occurs in which a uranium-238 atom forms a thorium-234 atom
and a helium-4 atom. Is this a chemical reaction or a nuclear reaction, and
how do you know?
A. A nuclear reaction, because one reactant became two products.
B. A nuclear reaction, because there was a change in the original
atom's nucleus.
O C. A chemical reaction, because two products formed from one
reactant.
O D. A chemical reaction, because there was a rearrangement of the
atom's electrons.
SUBMIT

B. A nuclear reaction, because there was a change in the original atom's nucleus

Explanation:

A nuclear reaction is the process in which a new nuclides or more than one new nuclides are produced from the collision of two nuclei or a subatomic particle from outside the system and an atomic nucleus

The products of a nuclear reaction must include the transformational change of a nucleus into another nuclide

Therefore, given that the reaction involves the transformation of the nucleus of the uranium-238 nucleus into two nuclides, including; thorium-234 and helium-4, nuclei, the process is a nuclear reaction

uranium-238 → thorium-234 + helium-4.

vapour or gas assuming atmospheriv pressure