I3- Ion Properties and Geometry

The video tutorial explains the molecular geometry of the triiodide ion (I3-). It begins with an introduction to the ion and its structure, followed by a detailed explanation of its Lewis structure, highlighting the octet rule and expanded octet for iodine. The tutorial then visualizes the molecular geometry, showing how the iodine atoms and lone pairs arrange themselves to form a linear shape. The AXE notation is used to further understand the geometry, identifying it as linear with a trigonal bipyramidal electron geometry. The video concludes with a summary of the key points discussed.

What is the charge of the triiodide ion?

• Neutral

• Negative

• Positive

• Variable

How many iodine atoms are present in the triiodide ion?

• One

• Four

• Two

• Three

In the Lewis structure of I3-, what is unique about the central iodine atom?

• It has fewer than eight electrons.

• It has an expanded octet.

• It has a standard octet.

• It is not bonded to any other atoms.

How many lone pairs are present in the I3- ion?

• Three

• Two

• One

• Four

What is the molecular geometry of the I3- ion?

• Linear

• Tetrahedral

• Bent

• Trigonal planar

What is the bond angle in the linear geometry of I3-?

• 120°

• 90°

• 109.5°

• 180°

What is the electron geometry of the I3- ion?

• Octahedral

• Tetrahedral

• Trigonal bipyramidal

• Linear

In AXE notation, what does 'E' represent?

• Central atom

• Number of lone pairs

• Number of bonded atoms

• Total number of atoms

What is the AXE notation for the I3- ion?

• AX3E2

• AX2E

• AXE3

• AX2E3

What is the bond angle in a linear molecular geometry?

• 109.5°

• 120°

• 90°

• 180°