Which of the following correctly distinguishes between chemical reactions and nuclear reactions?

• A. Both chemical and nuclear reactions only involve changes in electron configurations and never result in energy release.
• B. Chemical reactions change the nucleus of atoms, while nuclear reactions only rearrange electrons.
• C. Chemical reactions involve changes in electron arrangements and typically conserve mass, while nuclear reactions involve changes in the nucleus, can change one element into another, and may not conserve mass.
• D. Nuclear reactions always occur at room temperature, while chemical reactions require extremely high temperatures.

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the fundamental difference between chemical and nuclear reactions. Chemical reactions involve changes in the arrangement of electrons around atoms, while nuclear reactions involve changes in the nucleus of atoms.
2. Step 2: Recognize that chemical reactions typically conserve mass because they only rearrange electrons and atoms without changing the identity of the elements involved.
3. Step 3: Note that nuclear reactions can change one element into another by altering the number of protons in the nucleus, which can result in a change in the atomic number and sometimes a change in mass due to mass-energy conversion.
4. Step 4: Understand that energy release occurs in both chemical and nuclear reactions, but nuclear reactions generally release much more energy due to changes in nuclear binding energy.
5. Step 5: Evaluate the given options based on these principles to identify the correct statement that chemical reactions involve electron rearrangements and conserve mass, whereas nuclear reactions involve changes in the nucleus, can change elements, and may not conserve mass.