what is the total no. nuclides?which are they?

Answer 1

What I am assuming you mean by this question is how many total isotopes are there of each element in the periodic table.

The word "nuclide" means a specific atom with a specific atomic number and mass number. Ex. Uranium-238 and Uranium-235 are both uranium (atomic number of 92) but have different masses, so they are separate nuclides.

The word "isotope" means an atom that has the same number of protons as another atom (so they are the same kind of element) and a different number of neutrons (so they have a different atomic mass). For example, Carbon-12 has 6 protons and 6 neutrons, which add up to a mass of 12 amu. Carbon-14 has 6 protons and 8 neutrons, which add up to a mass of 14 amu. Having 6 protons makes both nuclides carbon, but having the different number of neutrons makes them isotopes, or different nuclides.

The total number...I have no idea, because I've never actually counted them. But, if you go to the Chart of the Nuclides on the web, that should help you out. Be aware, there are several sites that are selling copies of the chart, but do not actually have an interactive online chart. Try http://atom.kaeri.re.kr/

This chart is just a plot of protons vs. neutrons. Each row represents the same type of element, and each column represents elements with the same number of neutrons. The color tells which are stable and which are radioactive, and gives half-lives and such.