Inter-molecular Forces_Key Questions

Question 1

What is a molecular shape?

Answer 1

Molecular shapeis the three-dimensional arrangement of the atoms that constitute a molecule.

Question 2

What does a Molecular shape determine?

Answer 2

It determines several properties of a substance including its reactivity, polarity, stateof matter, colour, magnetism, and biological activity.

Question 3

What is Valence shell electron pair repulsion (VSEPR) theory?

Answer 3

a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms

Question 4

What is the premise of VSEPR?

Answer 4

Valence electron pairs surrounding an atom tend to repel each other, and will therefore adopt an arrangement that minimizes this repulsion, thus determining the molecule’s geometr

Question 5

What are Intermolecular Forces?

Answer 5

Intermolecular forces (IMFs) are forces of attraction or repulsion which act between neighboring particles (atoms, molecules, or ions).

Question 6

For a molecule to be considered polar it must have what two characteristics?

Answer 6

contain polar bonds (dipole bonds) - atoms with different electronegativities be non-symmetrical

Question 7

Describe Dipole Interactions.

Answer 7

Are electrostatic interactions between permanentdipolesin molecules.An example of a dipole-dipole interaction can be seen inhydrogen chloride(HCl): the positive end of a polar molecule will attract the negative end of the other molecule and influence its position.

Question 8

Describe Ion-dipole and ion-induced dipole Interactions.

Answer 8

Ion-dipole and ion-induced dipole forces are similar to dipole-dipole and induced-dipole interactions but involve ions, instead of only polar and non-polar molecules. Ion-dipole and ion-induced dipole forces are stronger than dipole-dipole interactions because the charge of any ion is much greater than the charge of a dipole moment. Ion-dipole bonding is stronger than hydrogen bonding.

Question 9

What is a hydrogen Bond?

Answer 9

A hydrogen bond is the attraction between the lone pair of an electronegative atom and a hydrogen atom that is bonded to either nitrogen, oxygen, or fluorine.The hydrogen bond is often described as a strong electrostatic dipole-dipole interaction.

Question 10

What are Dispersion forces?

Answer 10

Dispersion forces are very weak forces of attraction due to the formation of instantaneous dipoles because of the uneven distribution of electrons within molecules as they approach each other, The more electrons present in a molecule the bigger the dispersion forces will be. All molecules exhibit dispersion forces