Chem polarity

Question 1

What makes a molecule polar?

Answer 1

Polar molecules have an uneven charge distribution over the whole molecule (when it is considered three-dimensionally).

Uneven charge distribution occurs when the symmetry of the molecule (or arrangement of bonds around the central atom) means that bond dipoles do not cancel each other out.

This results in part of the molecule being slightly negative, and part is slightly positive.

(AKA a molecular dipole exists).

Question 2

Example of a polar molecule:

Answer 2

Water contains polar bonds.
The oxygen atoms in H20 are more electronegative than hydrogen atoms.

When the molecule = considered three-dimensionally, it has an uneven charge distribution; since the bond dipoles are unevenly arranged, they do not cancel.

Therefore, the molecule is polar.

Question 3

What makes a molecule non-polar?

Answer 3

When the charge distribution over the whole molecule is even, the molecule is non-polar.

This occurs when all the bond dipoles in the molecule are identical. (e.g, in tetrahedral, trigonal planar, and linear molecules).

Question 4

Non-polar

Answer 4

The charge distribution over the whole molecule is even

Question 5

Polar

Answer 5

The charge distribution over the whole molecule is uneven

(when it is considered three-dimensionally)