Chapter 3 Flashcards
ionic bonds
bond between two ions
the positive and negative charge hold the 2 together
complete gain/loss of electrons
usually for between metal and nonmetals
covalent bonds
an electron pair is shared between 2 atoms
nonpolar bonds
the electron pair is shared equally
polar bonds
the electron pair is shared unequally
coordinate covalent bonds
both the shared electrons come from 1 of the 2 atoms
formal charge
formal charge = (# valence electrons in unbonded atom) – (# of bonds) – (# of dots)
VSEPR theory
a system to predict the 3D arrangement of atoms in a molecule based on the number of bonds and lone electron pairs in their lewis structure
Steps to predict geometrical structure of a molecule using VSEPR theory:
intermolecular forces
- Electrostatic attractions between molecules
- Significantly weaker than covalent bonds
3 types of intermolecular forces
london dispersion forces
dipole-dipole interactions
hydrogen bonds
london dispersion forces
- a temporary attractive force due to the formation of temporary dipoles in a nonpolar molecule (as the electron cloud sways)
- weakest of the IM forces
- present in all atoms and molecules
- larger atom size = larger LD force
dipole-dipole interactions
- Occur between oppositely charged ends of polar molecules
- Stronger than London dispersion forces
- Evident in the solid and liquid phases but negligible in the gas phase due to the distance between particles
hydrogen bonds
- Specialized subset of dipole-dipole interactions
- Involved in intra and inter molecular attraction
- Hydrogen bonding occurs when hydrogen is bonded to one of three very electronegative atoms: fluorine, oxygen, or nitrogen