Question

What are isotopes? Give an example also.

Answer 1

isotopes are variants of a particular chemical element which differ in the number of neutrons and as a result of this, we can say that they do differ in the number of nucleons. The number of protons and neutrons which are present in the nucleus, together are known as nucleons.

Complete step by step answer:
Isotopes are the atoms of an element which have the same number of protons but different numbers of neutrons. In other words, you can say that the isotopes have the same atomic number, as the number of protons remain the same, but they have different atomic masses due to the different number of neutrons. And we already know that atomic mass is the sum of the number of protons and neutrons. So, as the number of neutrons are changed, the atomic mass also gets changed. Thus, it can be said that the isotopes are different forms of a single element.
There are $250$ isotopes of the $90$ naturally occurring elements and there are over $3200$ radio-active isotopes, some of which are natural and some are synthetic.
The chemical properties of isotopes of a single element tend to be nearly identical. However, the changes in the number of neutrons has such a significant effect on the size of the hydrogen nucleus.
On the other hand, the physical properties of isotopes are different from each other because these properties often depend on the atomic mass. Thus, this difference may be used to separate the isotopes of any elements from each other by using fraction distillation and diffusion. The atoms of an element that contain an unstable combination of neutrons and protons or excess energy in their nucleus are known as radioactive isotopes. This excess energy can be used in ways that the energy can be emitted from the nucleus in the form of gamma radiations, transferring one of the electrons to release it or to create and emit new particles from the nucleus. The examples of radioactive isotopes are uranium- $235$ and uranium- $238$.
Some other examples of isotopes are carbon -$12$, Carbon -$13$ and carbon -$14$. In this example the numbers $12,13{\text{ }}\operatorname{and} {\text{ 14}}$ represent the number of neutrons.

Note: Isotopes are either formed during their lifetime by getting neutrons or originate from the nuclear processes that do alter the atomic nuclei. Isotopes are used in medicines and in diagnostic purposes etc.