It tells you how many nucleons (protons and neutrons) there are in the nucleus.
atomic mass is the number of protons in that element molecule.
Rubidium is a metal element. Mass number of it is 85.
Sodium is a metal element. Mass number of it is 23.
90
isotopes just mean they have a different number of neutrons so if the..Mass number = # of protons + # of neutrons -they will have a different (greater) mass
The atomic number of an element is the number of protons in the nucleus of each atom of the element. Mass number is a property of a particular isotope of the element rather than of the element itself: The mass number is the sum of the numbers of protons and neutrons in the nucleus of each atom of the isotope.
Vanadium is a metal element. Mass number of it is 51.
Copper is a metal element. Mass number of it is 64.
Magnesium is a metal element. Mass number of it is 24.
The element with a mass number of 37 is chlorine (Cl).
The element with mass number 27 is cobalt, which has 27 as its atomic mass.
The element with a mass number of 52 is Chromium (Cr). It's atomic number is 24.