Molecular Geometry

Question 1

What is the geometry of a molecule with 2 groups around it? Bond angle?

Answer 1

planar (180)

Question 2

What is the geometry of a molecule with 3 groups around it? Bond angle?

Answer 2

trigonal planar (120)

Question 3

What is the geometry of a molecule with 4 groups around it? Bond angle?

Answer 3

tetrahedral (109.5)

Question 4

What is the geometry of a molecule with 5 groups around it? Bond angle?

Answer 4

trigonal bipyramidal (90, 120, 180)

Question 5

What is the geometry of a molecule with 6 groups around it? Bond angle?

Answer 5

octahedral (90, 180)

Question 6

What is the geometry of a molecule with 4 groups around it with one of them being a lone pair? Bond angle?

Answer 6

Trigonal pyramidal (less than 120)

Question 7

Which take up more space: lone pairs of electrons or bonded groups?

Answer 7

Lone pairs!

Question 8

What is the difference between electronic and molecular geometries?

Answer 8

Electronic geometry takes into account the lone pairs and molecular does not (only takes into account the atoms) → you still account for how they affect the shape though!
Think of different settings on the microscope

Question 9

What is important to remember about the geometry of double bonds? Which molecules are often like this? What does this mean for their hybridization?

Answer 9

When there is a double bond, all of the groups bonded to it are in the same plane
Elements attached to a carboxy group are in the same plan and are often sp2 hybridized, not sp3, because of the resonance (think keto/enol)