Multiple choice Which of the following elements tend to have their atomic masses in decimals? Elements having different isotopes Elements having different isobars Elements with variable valencies Elements with tendency to form cations Elements with tendency to form anions Reveal answer Fill a bubble to check yourself A Correct answer Explanation For an element that exists as isotope, the mass of the element is calculated as the weighted average of all naturally occurring isotopes of that element. The average mass is calculated in decimals.