Why do mass numbers have a trailing decimal? use the following words describe for credit isotopes protons neutrons electrons in carbon 13 HELP ME

a number without a decimal are generally not significant. Isotopes are atoms of same element which have the same atomic number but different number of neutrons. Isotopes of elements are represented in the following way: In an atom, the number of protons is equal to its atomic number.. An atom of an element is neutral in nature so atom contains the same number of protons and electrons.

Explanation:

it breaks and dirupture other materials and other sencews from the bottom

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.