What is the molecular geometry of H2O?
The Correct Answer and Explanation is:
The molecular geometry of H2O (water) is bent or angular. This shape is due to the arrangement of electron pairs around the oxygen atom, which follows the principles of VSEPR (Valence Shell Electron Pair Repulsion) theory.
In a water molecule, the central oxygen atom forms two single bonds with two hydrogen atoms. Oxygen has six valence electrons, and each hydrogen atom contributes one electron, making a total of eight valence electrons. These electrons are arranged in a way that minimizes the repulsion between electron pairs, as per VSEPR theory.
Oxygen also has two lone pairs of electrons that are not involved in bonding. These lone pairs exert repulsion on the bonding pairs, pushing the hydrogen atoms closer together. This causes the H-O-H bond angle to be approximately 104.5°, which is less than the ideal tetrahedral angle of 109.5° that would be seen in a molecule with four bonding electron pairs and no lone pairs.
The molecular geometry is bent, but it is important to distinguish between the shape (bent) and the electron geometry (tetrahedral). The electron geometry takes into account both the bonding and lone pairs, giving it a tetrahedral structure. However, since the lone pairs do not contribute to the molecular shape directly, the shape is considered bent.
This bent shape of water contributes to its many unique properties, such as its high boiling point, surface tension, and its ability to dissolve a wide range of substances. The polarity of the water molecule, due to the bent shape and the electronegativity difference between oxygen and hydrogen, makes it an excellent solvent for many ionic and polar substances.
