Chapter 24.1, Problem 1SSC

Interpretation Introduction

Interpretation:

The different types of radiation and their changes need to be explained.

Concept introduction:

Isotopes are atoms of same element whose number of neutrons is different. Isotopes having unstable nuclei are termed as radioisotopes. These unstable nuclei emit radiation to attain more stable atomic configuration is termed as radioactive decay.

Answer to Problem 1SSC

Three types of radiation, that is, alpha, beta and gamma.

Explanation of Solution

During radioactive decay, unstable atoms lose energy due to emission of radiation. Three types of radiation which are common are alpha $\left(\alpha \right)$, beta $\left(\beta \right)$ and gamma $\left(\gamma \right)$.

Alpha particle $\left(\alpha \right)$ possess the similar composition as the helium nucleus, that is, two protons and two neutrons and symbol is $\text{H}\text{e}$. The alpha radiation consists of stream of alpha particles. Alpha particles are slow moving as compared to other types of radiation because of their mass and charge.

Beta particle is a very fast moving electron which is emitted when a neutron is unstable nucleus converted into a proton. This particle is represented by $\left(\beta \right)$ or $e^{-}$. Their mass is so small compared with the mass of nuclei involved in nuclear reaction that it can be approximated to zero.

Gamma rays are photons, which are high-energy electromagnetic radiation. They are represented by the symbol $\gamma$. Because of no mass and charge, the emission of gamma rays does not changes atomic number of nucleus.

Conclusion

Three type of radiations, alpha $\left(\alpha \right)$, beta $\left(\beta \right)$ and gamma $\left(\gamma \right)$ occurs due to radioactive decay.