VSEPR Theory - lone electron pair influence

The video tutorial explains the influence of lone pairs on molecular geometry, using water, sulphur dioxide, and ammonia as examples. It discusses how lone pairs occupy more space and cause greater repulsions than bonded pairs, affecting molecular shapes. The VSEPR theory is used to predict molecular geometry, considering lone pair and bond pair repulsions. Sulphur dioxide is shown to have a bent shape due to lone pair repulsions, while ammonia's geometry is affected by its lone pair, resulting in a bond angle less than the typical tetrahedral angle.

How do lone pairs affect the molecular geometry of water?

• They cause the molecule to become linear.

• They have no effect on the bond angle.

• They increase the bond angle between hydrogen atoms.

• They reduce the bond angle between hydrogen atoms.

In the BX dy notation, what does 'Y' represent?

• The type of bonds present in the molecule.

• The total number of atoms in the molecule.

• The number of surrounding atoms bonded to the central atom.

• The number of lone pairs on the central atom.

How is a double bond treated in VSEPR theory?

• As two separate electron pairs.

• As a single electron pair.

• As a triple bond.

• As having no repulsion effect.

What shape does sulfur dioxide take due to lone pair repulsions?

• Tetrahedral

• V-shaped

• Trigonal planar

• Linear

What is the bond angle in ammonia due to lone pair repulsions?

• 120°

• 90°

• 107°

• 109.5°

How many electron pairs are around the central nitrogen atom in ammonia?

• Four

• Five

• Three

• Two

What would be the shape of ammonia if all electron pairs exerted similar repulsive forces?

• Trigonal planar

• Tetrahedral

• Bent

• Linear