SOLAR SYSTEM

Detailed explanation-1: -Ans. 1 There are 37 radioactive elements that are mentioned in the periodic table.

Detailed explanation-2: -One example of a radioactive substance is uranium. In nuclear power plants, uranium is used to produce electricity. When radioactive substances like uranium produce radiation, they also create a lot of heat. That heat causes water in the power plant to boil, turning turbines and creating electricity.

Detailed explanation-3: -Radionuclides undergo spontaneous disintegration into daughter nuclides with an associated emission of ionizing radiation in the form of alpha and beta particles and gamma rays. Daughter nuclides may be either stable or may themselves be radionuclides which also undergo radioactive decay.

Detailed explanation-4: -When igneous rocks crystallize, the newly formed minerals contain various amounts of chemical elements, some of which have radioactive isotopes.

Detailed explanation-5: -From the graph, we can see that after two half-lives, the remaining parent material will be 25% of the original amount, and the daughter material will be 75% of the original amount. Therefore, the rock is two half-lives old.