Michigan Test for Teacher Certification (MTTC) Secondary Integrated Science Practice test

What do nuclear reactions change in atomic nuclei?

1. Only the energy level

2. The atomic mass or chemical properties

3. Only the electrons surrounding the nucleus

4. The isotopes of atoms

The correct answer is: The atomic mass or chemical properties

Nuclear reactions fundamentally alter the structure of atomic nuclei, which directly impacts both the atomic mass and the chemical properties of the elements involved. When a nuclear reaction occurs, it can involve the transformation of one type of element into another, often resulting in a change in the number of protons and neutrons within the nucleus. This alteration in particle composition effectively changes the atomic mass because it modifies the total number of nucleons (protons and neutrons) within the nucleus. Additionally, as the number of protons changes, the element's identity may shift, leading to variations in chemical properties. For instance, if a nuclear reaction changes the number of protons, the element itself is transformed into a different element with distinct chemical behaviors and reactions. This complexity highlights the significant impact nuclear reactions have on the characteristics of substances at a fundamental level. While the other options suggest different scenarios, they do not encompass the full extent of what nuclear reactions accomplish. Changes to only energy levels or the configurations of electrons surrounding the nucleus do not accurately represent the core alterations made by nuclear reactions, which indeed transform the substance on a fundamental level. Moreover, while nuclear reactions do create isotopes, the broader implication regarding changes in atomic mass and properties encompasses more than just isotope