EVERYDAY SCIENCE

Detailed explanation-1: -Explanation: The quoted atomic mass on the Periodic Table is the WEIGHTED average of the individual isotopic masses. The higher the isotopic percentage, the MORE that isotope will contribute to the isotopic mass. For this reason, most masses that are quoted on the Table are non-integral.

Detailed explanation-2: -The nucleus of a given carbon atom will be one of the three possible isotopes discussed above. While the presence of isotopes affects the mass of an atom, it does not affect its chemical reactivity. Chemical behavior is governed by the number of electrons and the number of protons.

Detailed explanation-3: -Isotopes are atoms of the same element with different numbers of neutrons. Because they contain different numbers of neutrons, isotopes have different atomic masses. The average atomic mass of an element is calculated by taking the weighted average mass of the element’s naturally occurring isotopes.

Detailed explanation-4: -Stability of Isotopes. Atoms need a certain ratio of neutrons to protons to have a stable nucleus. Having too many or too few neutrons relative to protons results in an unstable, or radioactive, nucleus that will sooner or later break down to a more stable form. This process is called radioactive decay.