Question

All elements are unstable except the noble gases

True or False

Answer 1

True

Step-by-step explanation:

Noble gases already have the maximum number of valence electrons they can hold so they are the only stable group

Answer 2

Many elements only exist in an unstable or radioactive form. All non-natural or man-made elements are radioactive isotopes. Heavier isotopes tend to react more slowly than lighter isotopes of the same element. There are 254 known stable isotopes and 80 elements which have at least one stable isotope.