VSEPR Theory Part 3: Octahedral Family

TL;DR

The video explains the three-dimensional shapes that molecules with six surrounding atoms can take, including octahedral, square pyramidal, and square planar shapes.

Transcript

okay let's look at three-dimensional Vesper shapes for molecules with six things around the central atom molecules like these here as we've said these six things can be combinations of bonds and lone electron pairs we have six bonds like this one we can have five bonds and one lone electron pair we can have four bonds and two lone electron pairs fo... Read More

Key Insights

• 💠 Molecules with six bonds exhibit an octahedral shape to minimize electron repulsion.
• 🫀 The square pyramidal shape is formed when one atom from an octahedral molecule is replaced by a lone electron pair.
• 🫀 Square planar shapes occur when the top and bottom atoms of an octahedral molecule are replaced by lone electron pairs.
• ❎ Octahedral molecules have 90-degree bond angles, while square pyramidal and square planar molecules have slightly less than 90-degree angles.

Questions & Answers

Q: How do molecules with six bonds arrange themselves in three dimensions?

Molecules with six bonds form an octahedral shape, with the central atom in the middle and six surrounding atoms arranged around it, each bond having an angle of 90 degrees.

Q: What is the difference between an octahedral and a square pyramidal shape?

Octahedral shapes have six surrounding atoms, while square pyramidal shapes have five surrounding atoms and one lone electron pair, which causes a slight deviation from the 90-degree bond angles.

Q: How does a square planar shape differ from an octahedral shape?

Square planar shapes have four surrounding atoms and two lone electron pairs, resulting in a flat structure resembling a flying saucer or a drone.

Q: What determines the bond angles in a square pyramidal molecule?

The presence of a lone electron pair in a square pyramidal molecule causes the surrounding atoms to be slightly bent downwards, resulting in bond angles that are less than 90 degrees.

Summary & Key Takeaways

• Molecules with six bonds arrange themselves in an octahedral shape to minimize electron repulsion.

• IF5 molecules have a square pyramidal shape, with five surrounding atoms and one lone electron pair.

• Xenon molecules with four atoms and two lone electron pairs have a square planar shape.