Molecular Geometry of PI3

The video tutorial explains the molecular geometry and bond angles of phosphorus triiodide (PI3). It begins with the Lewis structure, highlighting the full octets of iodine and the lone pair on phosphorus. The molecular geometry is visualized as trigonal pyramidal, with a lone pair affecting the bond angles. The steric number and AXE notation are used to further understand the geometry, concluding with a bond angle of approximately 102 degrees.

What is the first step in determining the molecular geometry of PI3?

• Measure the bond lengths

• Draw the Lewis structure

• Identify the bond angles

• Count the number of atoms

How many valence electrons does each iodine atom have in PI3?

• Nine

• Eight

• Seven

• Six

What is the molecular geometry of PI3 when visualized in three dimensions?

• Tetrahedral

• Trigonal planar

• Linear

• Trigonal pyramidal

What is the electron geometry of PI3 when considering the lone pair?

• Linear

• Trigonal planar

• Trigonal pyramidal

• Tetrahedral

What is the steric number of the central phosphorus atom in PI3?

• Six

• Five

• Three

• Four

What is the bond angle in PI3 considering the lone pair effect?

• 120 degrees

• 90 degrees

• 109.5 degrees

• 102 degrees

In AXE notation, what does 'E' represent for PI3?

• Number of lone pairs

• Number of atoms bonded

• Total number of bonds

• Central atom

Which of the following best describes the role of lone pairs in determining molecular geometry?

• They have no effect

• They increase bond angles

• They decrease bond angles

• They change the type of bonds

What is the central atom in the PI3 molecule?

• Nitrogen

• Oxygen

• Phosphorus

• Iodine

Which molecular geometry is associated with a steric number of four and one lone pair?

• Trigonal planar

• Linear

• Tetrahedral

• Trigonal pyramidal