Isotope.
Ion
Look up the name on the periodic table and subtract the atomic number from the mass number (which is protons and neutrons). That will give you the number of neutrons.
Atoms of the same element cannot have different numbers of protons. Different numbers of protons mean different elements. An atom with the a different number of neutrons is called an isotope.
Number of protons + Number of neutrons = Mass number(number of nucleons)
Neutrons. If the differ in electrons they are not neutral and if they differ in protons then they are no longer the same element as the number of protons determines the name of the element.
Isotope.
The name of the element and the mass number (number of protons + neutrons) it is written e.g Uranium-235 or symbolically 235U
The number of neutrons in the nucleus of an atom of any isotope of an element is equal to the "atomic mass number", which is usually stated in a number immediately after a hyphen at the end of the element name in the name of the isotope, minus the atomic number. Because most elements have more than one stable isotope, the average number of neutrons in the mixture of isotopes of an element that occurs naturally is usually not an integer.
IsotopeIsotopes
'ISOTOPES'. The definitive statement is ' Isotopes of the same element have a different number of neutrons'. NB Do NOT confuse with 'Allotropes' . Allotropes of the same element exhibit different physical characteristics. The elements Sulphur and Phosphorus are the two classic examples of allotropes.
The Periodic Table of the Elements includes most of this information (but not the number of neutrons). The Chart of the Nuclides (or Table of the Isotopes) includes all of the information.
The element with 9 protons and 10 neutrons is fluorine-19 (F-19).