Atomic Bonding Test - 3

Expanded octet is formed between that compounds which have more than eight electrons in the valence shell around a central atom. Compounds with expanded octets around the central atoms of elements are in the third period and beyond.

For example, phosphorus commonly forms stable molecules and ions in which phosphorus is surrounded by more than an octet of valence electrons. Due to its large size, phosphorus as a central atom can violate the octet rule to form PF₅ and PF₆^-.

A hydrogen bond is formed by attractive force between the hydrogen attached to an electronegative atom of one molecule and an electronegative atom of a different molecule. Thus, because it is formed by attractive force thus ia a weakest bond.

Whenever a chemical bond is formed, there is a decrease in energy of the system.

In methane (ground state configuration: 1s², 2s², 2px¹ 2py¹), 1 carbon binds with 4 hydrogens. The carbon atom itself has only 2 electrons available for bonding in the 2p subshell.

In order for 4 hydrogens to bind, one electron of carbon gets excited from the 2s subshell into the 2p subshell, where it is available for bonding. Thus, a new 'hybridised orbital' called sp³ is formed.

Two atoms in the nitrogen molecule have three bonds between them and are joined by one sigma and two pi bonds.

Acetylene is formed by three sigma and two pi bonds.

From the above given substances chlorine molecule is formed by the weakest electrostatic forces of attraction.

The option (2) is incorrect. Because, electrovalent compounds are non-volatile in nature whereas covalent compounds are volatile in nature.