Here are the answers to your questions based on the provided information:
B)2. Nuclear Stability of Atoms:
- Helium-4: Stable nucleus
- Uranium-238: Unstable nucleus
- Thallium-216: Unstable nucleus
- Radon-219: Unstable nucleus
D)4. Nuclear Decay of Uranium-235: Uranium-235 will primarily undergo alpha decay.
E)5. New Atom Produced from Uranium-235 Decay: The new atom produced when Uranium-235 undergoes alpha decay is Thorium-231.
F)6. Types of Nuclear Decay for Thorium-231: Thorium-231 can undergo alpha and beta minus decay.
G)7. Type of Decay Making Thorium-231 More Stable: Alpha decay generally leads to a more stable nucleus compared to beta decay, so the answer is alpha.
If you have any more questions or need further clarification, feel free to ask!