Fluorine it has a atomic radius of 42
Answer:
Archaeologist use radioactive isotopes to determine the ages of various objects, rocks and materials. This is called radioactive dating. Radioactive isotope Carbon-14 is widely used for this dating process.
Scientists use radioactive isotopes in agriculture to monitor or study the uptake and use of essential nutrients by plants from the soil. This helps to determine viability, productivity and nutritious ability of the plants on a piece of land.
Geologists use radioactive isotopes to trace leaks in underground water storage, pipes. Radioactive isotopes are effective tracers because their radioactivity can be easily detected.
The correct answer is
A. Chain reaction
This is how the chain reaction works in a process of nuclear fission:
1) Slow-moving neutrons reach heavy, unstable, radioactive nuclei (such as Uranium-235)
2) The neutrons interact with the nuclei of Uranium, which break apart producing smaller nuclei and additional neutrons
3) The neutrons produced in the reaction are slowed down by a moderator (e.g. water) and they interact with new nuclei of Uranium, causing new fission reactions)
4) The new neutrons interact with new nuclei of Uranium, and so on...
