Structure And Bonding Flashcards
What is a covalent bond?
A covalent bond is formed when non-metal atoms shair pairs of electrons. This is the result of two positive nuclei being held together by their common attraction for the shared pair of electrons.
What are polar covalent bonds?
Polar covalent bonds are formed when the attraction of the atoms for the pair of binding electrons is different. This results in one atom being slightly negative and the other slightly positive.
What is a pure covalent bond/non-polar?
When two atoms of the same non metal element bond, the bonding electrons are shared equally. Some atoms with small differences in electronegativity (0.5<) can be non polar covalent.
What are ionic bonds?
Ionic bonds are the electrostatic attraction between positive and negative ions. Ionic compounds form lattice structures of oppositely charged ions.
What differences in electronegativity indicate what bond?
0-0.5~ non-polar
0.5-1.9~ Polar
2.0> Ionic
What are the intermolecular forces between molecules known as?
Van der Waals forces.
What are the three main van der waals forces?
London Dispersion Forces, permanent dipole to permanent dipole interactions, and hydrogen bonding.
How are London Dispersion Forces caused?
They are caused by the continual movement of electrons, which causes the temporary uneven distribution of charge at opposite sides if a molecule. This is known as a temporary dipole. This in turn induces a temporary dipole in a neighbouring molecule. The negatively charged sides of the molecule attracts the positive of a neighbouring atom and vice versa.
What does the strength of the London Dispersion Forces depend on?
The number of electrons within an atom or a molecule.
