Radioactivity and Its Types
This lesson covers the definition of radioactivity and the characteristics of radioactive elements. It explains the three types of radiation: alpha particles, beta particles, and gamma rays, along with their properties. The lesson also includes the concept of half-life and decay constants.
- 04:05 “electrical in neutral. That is they have no charge. They have negligible mass. They have high penetrating power in A and solid and several meters in lead. They are not deflected by magnetic field. This is because they ha...”
- 02:29 “That is anytime an alpha particle is emitted from a radioactive element. Then that means an atom of helium has been emitted and helium nuclei usually represented by 4 to H e. They are relatively I mass. They have little...”
- 01:39 “elements that disintegrate spontaneously and emit radiation from their nucleus. Example of radioactive elements are uranium, radium, polonium, ionium, sodium and so on and so forth. We have three types of radiations that...”
Particulate Nature of Matter
The lesson covers the distinction between physical and chemical changes, including examples. It explains the difference between atoms and molecules, describes the arrangement of particles in an atom, and defines atomic number, mass number, and isotopes. The calculation of relative atomic masses of a
- 18:15 “and electrons. Now, atoms ask the nucleus, which I said has two particles. We have the protons and the neutron that these two forms the nucleus. And outside the nucleus, there are some negative particles called the elect...”
- 20:57 “are negatively charged. While the protons are positively charged. So, if I have the same amount of proton in an atom, we have proton equal the neutron. So, if I have plus two and the other one, that's proton. The electro...”
- 21:48 “Let's remember that proton is positively charged. Electron is negatively charged. So, if they are the same. It means I have plus two minus two. Remember that neutron is neutral. So, an atom is electrically neutral. No ch...”