VSEPR and Bond Angles

Question 1

What does VSEPR theory say?

Answer 1

To minimize repulsions, valence electrons around the central atom are located as far as possible from the others.

Question 2

What is an electron group?

Answer 2

Any region of electrons. Can be a single, double, triple bond or a lone pair or a single electron.

Question 3

How many bonds are in a bonding group?

Answer 3

Any number. Can be single, double, or triple bonds

Question 4

When do ideal bond angles occur?

Answer 4

When all bonding groups are the same and connected to the same type of atom

Question 5

Does a double bond increase or decrease bond angles created by single bonds in the same molecule?

Answer 5

It decreases the single-bond angles because the greater electron density of a double bond repels electrons in single bonds more than the single bonds repel each other.

Question 6

Does a lone pair increase or decrease the angle between bonding pairs?

Answer 6

It decreases the angle between bonding pairs because a lone pair repels bonding pairs more than they repel each other.

Question 7

Why does a trigonal pyramidal molecule have bond angles of <109.5 degrees?

Answer 7

Because the one lone pair repels the other electron groups, which are bonds.