Intermolecular Forces Flashcards
What are the differences between covalent bonds and intermolecular forces?
-Covalent bonds are between atoms while intermolecular forces are between dipoles in compounds
-Covalent bonds are strong while intermolecular interactions are weak
What are three types of intermolecular forces?
-Induced dipole-dipole interactions (London Forces)
-Permanent dipole-dipole interactions
-Hydrogen Bonding
What properties are intermolecular forces responsible for?
Melting and Boiling points
Which intermolecular bond is stronger?
(weakest to strongest)
-1) ((weakest)) London
-2) Forces Permanent dipole-dipole interactions
-3) ((strongest)) Hydrogen bonds.
What molecules do London forces occur in?
All.
How are London forces/Induced dipole-dipole interactions created?
-Random movement of electrons create an instantaneous dipole. (Partial charge due to the increase/decrease of electrons around areas of nucleus)
-Instantaneous dipoles then induce oppositely charged dipoles on neighbouring molecules
Are London Forces temporary or permanent?
Temporary.
How can you make London Forces stronger?
The more electrons in a molecule, the larger the induced and instantaneous dipoles so the larger the dipole-dipole interactions.
What does the term “Van der Waal’s forces” mean?
Ambiguous name that can refer to both induced and permanent dipole-dipole interactions
What is a permanent dipole-dipole interaction?
Attraction between permanent dipoles in polar molecules
What are simple molecular lattices held together by?
Weak intermolecular forces
How strong are simple molecule’s intermolecular forces?
Weak, due to their intermolecular forces.
Why are simple molecules usually gases even in low temperatures?
The energy in low temperatures are usually enough to overcome their intermolecular forces
Which, out of polar and non-polar molecules, are soluble when in a polar solvent?
Polar molecules due to the opposite charges of the solvent and molecule being attracted to one another.
Which, out of polar and non-polar molecules, are soluble when in a non-polar solvent?
Non-polar molecules as they are broken by interactions with the non-polar solvent