Which of the following elements is not likely to form bonds?

gold
oxygen
neon
mercury

hint: heard of noble gases?

To determine which of the following elements is not likely to form bonds, we need to consider their electron configurations.

Gold (Au) is in the d-block of the periodic table and has a partially filled d-orbital, which enables it to form both ionic and covalent bonds.

Oxygen (O) is in the p-block and has six valence electrons. It is highly reactive and readily forms covalent bonds with other elements.

Neon (Ne) is a noble gas and is known for its stable electron configuration. Noble gases have a complete valence shell, making them highly stable and unlikely to form bonds.

Mercury (Hg) is in the d-block and has a partially filled d-orbital, making it capable of forming bonds, particularly with electronegative elements like oxygen and halogens.

Based on this information, neon (Ne) is the element that is least likely to form bonds. It belongs to the noble gas family and already has a stable electron configuration. Therefore, neon does not readily form chemical bonds.