Chapter 6: Shapes Of Molecules And Intermolecular Forces

Question 1

What makes a bond polar?

Answer 1

A covalent bond forms between 2 atoms with different electronegativities. The bonded electron pair is shared unequally between the bonded atoms. The atom with the higher electronegativity will attract the bonding electrons more making it slightly negatively charged and the other atom will be slghtly positively charged.
This creates a permanent dipole within the molecule.

Question 2

What happens to the solvency of a polar solute and polar solvent?

Answer 2

If the substance is polar and the solvent is also polar, it will dissolve easily. Oppositely charged parts of the solvent and solute molecules are attracted causing solute particles to move away from each other. They are then surrounded by the solvent and will be dissolved.

Question 3

What happens to the solvency of a non-polar solute and polar solvent?

Answer 3

There isnt enough attraction between the chsrged areas of the solvent andthe non-polar solute to pull particles apart and make it dissolve.

Question 4

What are the effects of position on the periodic table on the boiling point of a substance?

Answer 4

If the element is lower down in the same group, they will have more electrons. This leads to the formation of stronger id-id interactions which increases the substances boiling point.

Question 5

Why is a molecule with nitrogen, oxygen, flourine, hydrogen more likely to have a higher boiling point than other molecules?

Answer 5

There will be hydrogen bonding present which is stronger than even dipole-dipole forces in other molecules.