Chapter 24.2, Problem 13SSC

Interpretation Introduction

Interpretation:

The stability of an isotope needs to be explained if the number of neutron and protons are known.

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.

Explanation of Solution

To a certain degree, nuclei's stability can be related to its ratio of number of neutrons and protons. Atoms having lower atomic numbers (<20), the most stable nuclei are those with neutron-to-proton ratio of 1:1. For example, helium has two neutrons and two protons, so neutron to proton ratio is 1:1. Hence, helium is the stable nuclei.

Conclusion

Neutron to proton ratio determines the stability of nuclei.