A level chem dipole question help needed!

FM1/FP1

im wondering why the answer is A even though sulfur is less electronegative than chlorine

(edited 11 months ago)

Reply 1

bl0bf1sh

Original post by FM1/FP1

im wondering why the answer is A even though sulfur is less electronegative than chlorine

Can you draw (or google) the structures of each of the molecules?
(shapes, lone pairs included)

(edited 11 months ago)

Reply 2

FM1/FP1

Original post by bl0bf1sh

Can you draw (or google) the structures of each of the molecules?
(shapes, lone pairs included)

oh, is it because sf6 has the s-f bonds opposite each other so they kinda cancel out?

Reply 3

TypicalNerd

Original post by FM1/FP1

oh, is it because sf6 has the s-f bonds opposite each other so they kinda cancel out?

Correct.

Can you determine whether similar logic applies to any of the other molecules from the list?

Reply 4

FM1/FP1

Original post by TypicalNerd

Correct.

Can you determine whether similar logic applies to any of the other molecules from the list?

i guess they could apply to all the molecules to a certain degree but not as bad as the sf6 one since the other molecules dont have the bonds directly opposite

Reply 5

charco

Study Forum Helper

Original post by FM1/FP1

i guess they could apply to all the molecules to a certain degree but not as bad as the sf6 one since the other molecules dont have the bonds directly opposite

What is the shape of ClF₃?

I'm going to edit my own question.

Cl has 7 electrons
Each F shares one pair, i.e. contributes 1 electron per fluorine = 3 electrons
Total electrons around the chlorine = 10, arranged in 5 pairs
This means that there are 3 bonding pairs and 2 lone pairs
The electronic shape is trigonal bipyramidal.
To reduce inter-electron repulsion the two lone pairs should adopt equatorial positions. (this keeps the lone pairs further from more other pairs of electrons)
The molecular shape is "T" shaped.
This makes the molecule polar.

(edited 11 months ago)