There is not an isotope number on the Periodic Table of Elements. There is an atomic number (# of protons) and the average Atomic Mass. The average atomic mass is the weighted average of all the naturally occurring isotopes for each element. This number is not a whole number, because it is an average of all the isotopes for a particular element.
A normal periodic table does not list isotopes, but elements, almost all of which occur in more than one isotope, and there is probably at least one radioactive isotope for every element. Instead of the periodic table, a table of nuclides is needed to answer this question.
The group number is an identifier used to describe the column of the standard Periodic Table in which the element appears.
Elements on a periodic table are ordered based on their atomic number, which represents the number of protons in the nucleus of an atom. This yields a unique and systematic arrangement of elements according to their properties.
atomic number
atomic number (or number of protons)
A normal periodic table does not list isotopes, but elements, almost all of which occur in more than one isotope, and there is probably at least one radioactive isotope for every element. Instead of the periodic table, a table of nuclides is needed to answer this question.
No; T may be a symbol for the tritium an isotope of hydrogen.
The group number is an identifier used to describe the column of the standard Periodic Table in which the element appears.
The atomic number is the number of protons in the nucleus of an element. It defines the element. No two different elements can have the same number of protons. It is used to lay out the periodic table because the table shows the elements in increasing numbers of protons.
Atomic number
The periodic table used to be arranged by increasing atomic mass. Now, it is arranged by increasing atomic number (number of protons in an atom of element).
"H" stands for Hydrogen on the periodic table.
The atomic number 81 on the periodic table corresponds to the element Thallium (Tl). It is a soft, malleable metal that is often used in electronic components, alloys, and in some types of thermometers.
Atomic number on the basis of Modern periodic law as on the view of Henry Mosely
Elements on a periodic table are ordered based on their atomic number, which represents the number of protons in the nucleus of an atom. This yields a unique and systematic arrangement of elements according to their properties.
number of protons
atomic number