Final answer:
The least stable option is a noble gas like Neon or Helium because their outermost shell is already filled with electrons, making them very stable and unreactive. A neutral atom of N is more stable than the noble gas option because it has an unfilled outer shell and can form covalent bonds to achieve stability. ionically bonded sodium chloride (NaCl) is more stable than a neutral atom of N because both Na and Cl have filled outer shells due to the transfer of electrons. The most stable option is covalently bonded methane (CH4) because all the atoms share electrons to achieve stability.
Step-by-step explanation:
The stability of atoms depends on whether or not their outer-most shell is filled with electrons. If the outer shell is filled, the atom is stable. Atoms with unfilled outer shells are unstable and will usually form chemical bonds with other atoms to achieve stability.
A. Noble gas like Neon or Helium is the least stable because their outermost shell is already filled with electrons, making them very stable and unreactive.
B. A neutral atom of N would be more stable than option A because it has an unfilled outer shell and can form covalent bonds to achieve stability.
C. Ionically bonded sodium chloride (NaCl) is more stable than option B because Na donates an electron to Cl to form Na+ and Cl-, and both ions now have filled outer shells.
D. Covalently bonded methane (CH4) is the most stable among the options because all the atoms share electrons to achieve stability.