# Why are their bond angles so different? ### Why are their bond angles so different?

Because a lone pair of electrons requires more space than a bonding pair, the molecular geometry distorts to afford the lone pair greater space, with the result that bond angles are smaller than those of the ideal geometry.

### What makes a bond angle ideal?

Bond Angles. ... The bond angle can help differentiate between linear, trigonal planar, tetraheral, trigonal-bipyramidal, and octahedral. The ideal bond angles are the angles that demonstrate the maximum angle where it would minimize repulsion, thus verifying the VSEPR theory.

### Why is it 109.5 The ideal bond angle?

VSEPR Theory: Valence Shell Electron Pair Repulsion Theory. ... VSEPR theory predicts methane is a perfect tetrahedron with all H-C-H bond angles equal at 109.5o, because the hydrogen atoms repel equally, and because this geometry puts the greatest distance between all four bonded electrons pairs.

### What are the factors affecting bond angle?

(i) Repulsion between atoms or groups attached to the central atom may increase or decrease the bond angle. (ii) In hybridisation as the s character of the s hybrid bond increases, the bond angle increases. (iii) By increasing lone pair of electron, bond angle decreases approximately by 2.5%.

### Why are bond angles not ideal?

Bond angles will deviate from their ideal values according to the rule that lone pairs repel other electrons more strongly than bonding pairs. Although lone pairs are clearly smaller than atoms, they need to be closer to the nucleus of an atom than a bonding pair.

### Do double bonds affect bond angle?

Like lone pairs of electrons, multiple bonds occupy more space around the central atom than a single bond. ... Double and triple bonds distort bond angles in a similar way as do lone pairs. Due to the stronger repulsion, double and triple bonds occupy similar positions as lone pairs in groups with 5 and 6 electron groups.

### What is the ideal angle of the HNH bond?

about 107 degrees Since lone pairs take more space, the H-N-H bond angle is reduced from 109.5 degrees to about 107 degrees. The geometry of ammonia is trigonal pyramidal rather than tetrahedral since the lone pair is not included.

### Why does the bond angle remain the same at 107 ∘?

The excited molecule remains bent largely due to the strong effect of two electrons in 3 a X 1 counteracting the single electron in 4 a X 1. The bond angle is almost unchanged at 107 ∘, but the energy gap will be larger than in B H X 2 or N H X 2, again as observed.

### Why are bond angles of CH4 and H2O different?

The difference in the bond angles of CH4, H2O and NH3 can be explained using VSEPR Theory ( Valence Shell Electron Pair Repulsion theory ). According to VSEPR theory the rupulsive force between bond pairs and lone pairs are not same. But, repulsive force act as follows : Bond pair - Bond pair < Bond pair-Lone pair < Lone pair -Lone pair .

### What is the bond angle of B H x 2?

The bond angle is almost unchanged at 107 ∘, but the energy gap will be larger than in B H X 2 or N H X 2, again as observed. The bond angles of N H X 2, N H X 2 X − and N H X 2 X + are all very similar, 103 ∘, 104 ∘, and 115 ∘ respectively.

### Why does the bond angle of water decrease?

It is clear that as the bond angle for water is neither 109.4 ∘, 120 ∘, nor 180 ∘ that s p X 3, s p X 2 or s p hybridisation will not explain the bond angles. Furthermore, the UV photoelectron spectrum of water, which measures orbital energies, has to be explained as does the UV absorption spectra.