Phosphorus Trichloride and Ammonium Ion Concepts

The video tutorial guides viewers through predicting the shapes of different chemical species by drawing their Lewis structures. It covers three compounds: a carbon-centered molecule with fluorine and hydrogen, phosphorus trichloride, and the ammonium ion. For each, the tutorial explains how to count valence electrons, draw the skeletal structure, distribute electrons, and determine molecular geometry and polarity. The video emphasizes understanding the relationship between electron distribution and molecular shape.

What is the first step in predicting the shape of a molecule?

• Identify the type of bonds

• Draw the Lewis structure

• Determine the molecular weight

• Measure the bond angles

How many valence electrons are present in the first compound discussed?

• 26

• 24

• 28

• 30

What is the geometry of the first compound?

• Bent

• Linear

• Trigonal planar

• Tetrahedral

Why is the first compound considered polar?

• It has a lone pair of electrons

• It has different atoms attached to the central atom

• It has equal distribution of charge

• It has a symmetrical shape

How many valence electrons are in phosphorus trichloride?

• 30

• 24

• 26

• 28

What is the geometry of phosphorus trichloride?

• Square planar

• Tetrahedral

• Linear

• Trigonal pyramidal

What effect does the lone pair have on the shape of phosphorus trichloride?

• It has no effect on the shape

• It results in a trigonal pyramidal shape

• It causes the molecule to be non-polar

• It makes the molecule linear

How many valence electrons are in the ammonium ion?

• 7

• 9

• 6

• 8

What is the geometry of the ammonium ion?

• Linear

• Tetrahedral

• Bent

• Trigonal planar

Why does the ammonium ion have a positive charge?

• It has more protons than electrons

• It has more electrons than protons

• It has an extra electron

• It has a missing proton