What Shapes Do Simple Molecules Make

The video tutorial explains the 3D nature of molecules, focusing on electron pair repulsion theory. It covers the tetrahedral shape of methane (CH4) and ammonium ion (NH4+), both having four bonding pairs. The tutorial then discusses ammonia (NH3), which has a pyramidal shape due to one lone pair, reducing the bond angle to 107 degrees. Finally, it examines water (H2O), which has two lone pairs, creating a bent shape with a bond angle of 104 degrees. The video emphasizes how lone pair repulsion affects molecular geometry.

What is the bond angle in a tetrahedral molecule like methane?

• 180 degrees

• 90 degrees

• 109.5 degrees

• 120 degrees

How does the shape of the ammonium ion (NH4+) compare to methane (CH4)?

• It is bent

• It is also tetrahedral

• It is square planar

• It is linear

What is the bond angle in ammonia (NH3) due to the presence of a lone pair?

• 104 degrees

• 107 degrees

• 109.5 degrees

• 120 degrees

What shape does water (H2O) form due to its lone pairs?

• Tetrahedral

• Trigonal planar

• Linear

• Bent

Why do lone pairs cause a greater repulsion than bonding pairs?

• They are negatively charged

• They are closer to the nucleus

• They are larger in size

• They have more energy