C O H Bond Angle In Alcohol Is Less Than Tetrahedral Angle

Both c o h and c o c bond angles in alcohols and ethers respectively are sp 3 hybridised.

C o h bond angle in alcohol is less than tetrahedral angle. Coh bond angle in alcohol is less than tetrahedral angle of 109 5 0 coc bond angle in ether is more than tetrahedral angle of 109 5 0. Due to the repulsion between the unshared electron pairs of oxygen the bond angle of c o h bonds in alcohols is slightly less than the tetrahedral angle 109 28. In general the lone pairs on o tend to repel the bond pairs and results in lower bond angles than 1 0 9 in case of alcohols but in ethers the c o c bond angle is slightly more than this i e nearly 1 1 0. In alcohol molecule both the c and o atom are sp3 hybridized.

The bond angle in regular tetrahedral is 1 0 9 2 8. H in alchols is slightly less than tetrahedral is slightly less than tetrahedral angle 109 28. In both the cases oxygen atoms contain two bond pairs and two lone pairs of electrons and are oriented in a tetrahedral shape around the oxygen atom. The c o h bond angle in alcohols is slightly less than the tetrahedral angle because of the repulsion between the two lone pairs of electrons on oxygen atoms as these pairs pushes the c o bonds closer to each other.

However in the case of the oxygen atom in an alcohol i assume that s the bond angle you are looking at the substituents on the oxygen are a carbon atom a hydrogen atom and two lone pairs. In ethers the c o c bond angle is slightly greater than tetrahedral angle. In alcohols two lone pair of electrons are present. Why is the c o h bond angle in alcohols slightly less than the tetrahedral angle whereas the c o c bond angle in ether is slightly greater.

It is due to the repulsion between the unshared electron pairs of oxygen. This sigma bond is formed due to the overlap of an sp 3 hybridized orbital of carbon with an sp 3 hybridized orbital of oxygen. The c o h bond angle in alcohols is slightly less than the tetrahedral angle 109 o 28 due to the repulsion between the two lone pairs of electrons of oxygen which pushes the c o and o h bonds closer to each other. Why c o h bond angle of aliphatic alcohol is less than pure tetrahedral bond angle.

In a perfect tetrahedral like ch 4 all four hydrogen groups are distributed around the carbon atom equally leading to the bond angle of 109 5 deg. For example in methanol c o h bond angle is 108 9. Ncert dc pandey sunil batra hc verma pradeep. Therefore three is comparatively more repulsion and less and angle.