Atoms of the same element that have different numbers of neutrons Know the two ways in which an isotope is written What is the mass number of an atom? The mass number is the sum of the number of protons and neutrons in an atom. What is the average atomic masses? The atomic mass is ...
A new element was recently discovered and found to have an atomic weight of 342.38 amu. This element has two isotopes, the lighter of which has a mass of 340.91 amu and an abundance of 68.322%. What is the mass of the heavier isotope?
number of protons defines the element Number of Neutrons Equation # Neutrons = Mass Number (A) - Atomic Number (Z) Charge of atom equation Charge = #protons - #electrons Isotopes are atoms that have the same number of protons but have different number of neutrons. (Or, isotopes have the ...