In 1893, which Swiss chemist was the first to understand the molecular structures of inorganic substances - chemical compounds that do not contain carbon?

Alfred Werner

The correct answer is option 1. Alfred Werner.

Alfred Werner was a Swiss chemist who made significant contributions to the field of coordination chemistry. In 1893, he proposed the coordination theory, which marked a groundbreaking development in understanding the molecular structures of inorganic substances, particularly coordination compounds.

1. Coordination Compounds:

Coordination compounds are molecules or ions in which a central metal atom or ion is bonded to ligands (atoms, ions, or molecules) through coordinate covalent bonds. These compounds are prevalent in inorganic chemistry and have diverse applications, including catalysis and medicine.

2. Coordination Theory:

Before Alfred Werner's work, the understanding of the structures of coordination compounds was limited. Werner's breakthrough came when he proposed a new theory to explain the observed structures and properties of these compounds. He introduced the concept of coordination numbers, which represents the number of ligands attached to the central metal atom. Werner's theory explained how the ligands coordinate around the metal center.

3. Coordination Numbers:

Werner identified different coordination numbers, such as 2, 4, 6, etc., depending on the arrangement of ligands around the central metal atom. For example, in hexacoordinate complexes, six ligands surround the central metal atom.

4. Chelation:

Werner also introduced the concept of chelation, where a ligand forms multiple bonds to a metal ion at different points, creating a ring structure. This explained certain observed stability and isomerism in coordination compounds.

5. Impact and Recognition:

Alfred Werner's coordination theory was widely accepted and had a profound impact on inorganic chemistry. In 1913, he was awarded the Nobel Prize in Chemistry for his work on the linkage of atoms in molecules, specifically large organic molecules.

Alfred Werner's contributions laid the foundation for the systematic understanding of the structures of coordination compounds, paving the way for further developments in the field of coordination chemistry.