Molecular Geometry and VSEPR Theory

The video explains the VSEPR theory, which predicts molecular geometry based on electron group repulsion. It covers various geometries like linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral. The impact of lone pairs on molecular geometry is also discussed, with examples like ammonia and water. The video concludes with practice exercises on assigning molecular geometries.

What is the fundamental principle behind VSEPR theory?

• Neutrons influence electron group arrangement.

• Electron groups attract each other.

• Electron groups repel each other.

• Protons repel electron groups.

Which molecular geometry is characterized by a 180° bond angle?

• Trigonal planar

• Tetrahedral

• Octahedral

• Linear

In a trigonal planar geometry, what is the bond angle between electron groups?

• 109.5°

• 90°

• 180°

• 120°

Which molecule has a tetrahedral molecular geometry?

• BF3

• BeCl2

• CH4

• CO2

What is the geometry called when five electron groups are arranged around a central atom?

• Trigonal bipyramidal

• Square planar

• T-shaped

• Bent

In an octahedral geometry, what is the bond angle between any two groups?

• 120°

• 60°

• 90°

• 180°

How does the presence of a lone pair affect the molecular geometry of ammonia?

• It becomes square planar.

• It becomes trigonal pyramidal.

• It becomes linear.

• It becomes octahedral.

What is the molecular geometry of water (H2O)?

• Linear

• Tetrahedral

• Trigonal planar

• Bent

Which molecular geometry is described as 'seesaw'?

• Four bonding groups and one lone pair

• Three bonding groups and two lone pairs

• Two bonding groups and three lone pairs

• Five bonding groups and no lone pairs

What is the molecular geometry of the nitrate ion?

• Square planar

• Tetrahedral

• Trigonal pyramidal

• Trigonal planar