MCQ Detailed View

Hydrogen peroxide (H₂O₂) is a simple molecule composed of two hydrogen atoms and two oxygen atoms. Its molecular structure is best described as a non-polar molecule in terms of its overall charge distribution, although the molecule contains polar O–H bonds.

The H–O–O–H structure of hydrogen peroxide is non-planar, with a dihedral angle of about 111° between the planes formed by the two O–H bonds. This twisted or “skewed” structure reduces repulsion between lone pairs of electrons on the oxygen atoms. As a result, the molecule achieves stability and minimized electron-pair repulsion.

Even though the O–H bonds are polar due to the electronegativity difference between oxygen and hydrogen, the overall molecular symmetry causes the dipole moments to cancel partially, giving hydrogen peroxide a non-polar character in terms of global polarity in some references. However, it is important to note that in many cases, H₂O₂ is considered polar in terms of its chemical reactivity and hydrogen bonding.

Hydrogen peroxide is widely used as an oxidizing agent, bleaching agent, and disinfectant. Its structure and polarity influence reactivity, solubility, and intermolecular hydrogen bonding. The dihedral angle and non-planar structure are essential to understand for chemical reactions, decomposition pathways, and interactions in aqueous solutions.

Understanding the molecular structure of H₂O₂ is a fundamental concept in physical chemistry, as it illustrates how electron repulsion, bond angles, and molecular geometry determine molecular properties.