Which answer choice best explains why atoms of carbon-14 (c-14) are unstable?

a. atoms of c-14 have too many negatively charged electrons and too few positively charged protons.

b. atoms of c-14 have too many positively charged protons and too few negatively charged electrons.

c. the attractive force that the protons in the nuclei of c-14 atoms generate is not strong enough to overcome the repulsive force that the neutrons generate.

d. the attractive force that the neutrons in the nuclei of c-14 atoms generate is not strong enough to overcome the repulsive force that the protons generate.

THE ANSWER IS dD. The attractive force that the neutrons in the nuclei of C-14 atoms generate is not strong enough to overcome the repulsive force that the protons generate.

Answer is: D. The attractive force that the neutrons in the nuclei of C-14 atoms generate is not strong enough to overcome the repulsive force that the protons generate.

Atoms are made of protons (positive charge), neutrons (neutral charge) and electrons (negative charge).

Atomic number (Z) of atom ¹⁴C is 6, it means it has 6 protons and 6 electrons, because atom has neutral charge.

Mass number (sum of protons and neutrons) of atom ¹⁴C is 14, it means it has 8 neutrons in the nucleus of the atom.

n(p⁺) = 6.

n(e⁻) = 6.

n(n°) = 14 - 6.

n(n°) = 8; number of neutrons in carbon atom ¹⁴C.