The bond angle of hydrogen sulphide (H2S) is approximately 92 degrees. This angle is slightly smaller than the ideal tetrahedral angle of 109.5 degrees due to the lone pair of electrons on the sulfur atom that creates repulsion and decreases the bond angle.
The bond angle of hydrogen sulphide can be affected by the presence of lone pairs on the central atom, the electronegativity of the atoms involved, and the size of the atoms. As the lone pairs increase or the electronegativity difference between the atoms increases, the bond angle decreases. Larger atoms also tend to have larger bond angles.
The bond angle of hydrogen sulphide is smaller than that of water (104.5 degrees) due to the presence of two lone pairs on the sulfur atom, which create more repulsion and decrease the bond angle. In comparison, water has two bonding pairs and two lone pairs, resulting in a slightly larger bond angle.
The bond angle of hydrogen sulphide is largely determined by its molecular geometry and the factors mentioned above. However, it can be slightly altered by changes in temperature and pressure. Higher temperatures and pressures can increase the bond angle due to the increased kinetic energy of the molecules.
The bond angle of hydrogen sulphide is important because it affects the molecule's overall shape and properties. For example, the bent shape of H2S gives it a dipole moment, making it polar and allowing it to form hydrogen bonds with other molecules. This is significant in understanding its chemical and physical properties, as well as its role in biological systems.