Molecular Geometry and AXE Notation

The video explains the molecular geometry of BF3, starting with its Lewis structure. Boron trifluoride is an exception to the octet rule, having only six valence electrons around the central boron atom. The video visualizes the trigonal planar shape of BF3, with bond angles of 120°. It also covers the concept of steric number and AXE notation, showing that BF3 has a steric number of three with no lone pairs, resulting in the same electron and molecular geometry.

What is the first step in determining the molecular geometry of BF3?

• Use AXE notation

• Determine the steric number

• Draw the Lewis structure

• Identify the bond angles

Why is Boron an exception to the octet rule in BF3?

• It can have more than eight electrons

• It can be stable with six electrons

• It has a full d-orbital

• It does not form bonds

What is the molecular geometry of BF3?

• Bent

• Tetrahedral

• Trigonal planar

• Linear

How do the fluorine atoms in BF3 arrange themselves around the boron atom?

• As far apart as possible in a plane

• In a square planar shape

• In a straight line

• In a tetrahedral shape

What is the bond angle in the trigonal planar geometry of BF3?

• 120°

• 109.5°

• 90°

• 180°

What is the steric number of BF3?

• Three

• Two

• Four

• Five

Why does BF3 have the same electron and molecular geometry?

• Because it has lone pairs

• Because it has no lone pairs

• Because it has a high steric number

• Because it is a polar molecule

In AXE notation, what does the 'X' represent for BF3?

• The lone pairs

• The bond angles

• The central atom

• The surrounding atoms

What is the AXE notation for BF3?

• AX2E2

• AX3

• AX2E

• AX4

How can you determine the molecular geometry of BF3 using AXE notation?

• By counting the number of lone pairs

• By memorizing AX3 as trigonal planar

• By calculating the bond angles

• By identifying the central atom