In which year did Langmuir reform the Lewis concept by abandoning the idea of a stable cubical arrangement of the octet and introducing the term ‘covalent bond’?

1919

The correct answer is option 1. 1919.

In 1919, Irving Langmuir made significant contributions to the understanding of chemical bonding by reforming Gilbert Lewis's concept of the octet rule. Gilbert Lewis had proposed the octet rule in 1916, suggesting that atoms tend to achieve a stable electron configuration by sharing or transferring electrons to attain a full outer shell of eight electrons.

Langmuir modified this concept by abandoning the idea of a stable cubical arrangement of the octet. He introduced the term 'covalent bond' to describe the sharing of electrons between atoms. The covalent bond is a type of chemical bond in which electrons are shared between atoms to achieve a more stable electron configuration.

Langmuir's work was crucial in refining our understanding of chemical bonding and laying the foundation for the modern understanding of covalent bonds and molecular structures. The covalent bond concept is fundamental in explaining the formation of molecules and the sharing of electrons between atoms to achieve stability. Langmuir's contributions played a significant role in the development of molecular chemistry and our understanding of the nature of chemical bonds.