What are the lone pair angles in H2O according to VSEPR theory?

  • Thread starter Thread starter alingy1
  • Start date Start date
  • Tags Tags
    Angles Pair
Click For Summary
SUMMARY

The angles between lone pairs in H2O, according to VSEPR theory, are approximately 104.45 degrees. While the bond angles in H2O are often cited as 109.5 degrees, this value applies to a tetrahedral arrangement, which does not accurately describe the bent geometry of the water molecule. The presence of lone pairs results in a repulsion that alters the angles, leading to the smaller angle of 104.45 degrees. This conclusion is supported by the understanding that lone pairs occupy more space than bonding pairs, affecting the overall molecular geometry.

PREREQUISITES
  • Basic understanding of VSEPR theory
  • Knowledge of molecular geometry
  • Familiarity with bond angles in tetrahedral structures
  • Concept of lone pair repulsion in molecular shapes
NEXT STEPS
  • Study the impact of lone pair repulsion on molecular geometry
  • Learn about the differences between tetrahedral and bent molecular shapes
  • Explore examples of other molecules with lone pairs and their bond angles
  • Investigate the application of VSEPR theory in predicting molecular shapes
USEFUL FOR

Chemistry students, educators, and anyone interested in molecular geometry and VSEPR theory will benefit from this discussion.

alingy1
Messages
325
Reaction score
0

Homework Statement



What are the angles between lone pairs in H2O? I know that the bonds are separated by 109.5°. What about the lone pair angles? I googled everything. I found nothing. I cannot directly assume it is 109.5°... I have a basic knowledge of VSEPR.
 
Physics news on Phys.org
alingy1 said:
I know that the bonds are separated by 109.5°.
Really? I thought it was 104.45 degrees.
In VSEPR, both bonding and lone pairs should be distributed approximately along the corners of a tetrahedron. Lone pairs are a bit more space filling than bonding pairs, so that the angle between the lone pairs is somewhat larger.
 
I will double check my answers before posting.
 
Last edited:
Treedude said:
H2O is bent. 109.5

H2O is bent, but 109.5 is incorrect. Water molecule is not tetrahedral. DrDu already posted a correct value.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
4K
Replies
4
Views
4K
Replies
4
Views
29K
  • · Replies 5 ·
Replies
5
Views
14K
  • · Replies 2 ·
Replies
2
Views
13K
  • · Replies 1 ·
Replies
1
Views
12K
  • · Replies 3 ·
Replies
3
Views
9K
  • · Replies 1 ·
Replies
1
Views
3K
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K