chapter 3 Flashcards
(48 cards)
polarity is the distribution of
electrical charge over bonded atoms
a polar bond is formed between
two atoms with a difference in electronegativities by sharing electrons
a covalent bonds polarity depends on the
electronegativity difference between the bonding atoms
how do you determine molecular polarity when a molecule has multiple bonds between multiple atoms
- polarity of bonds within molecule
- geometry and symmetry
polar molecule
molecule where electrons are uneven, so one end has a positive charge and one has a negative
example of polar molecule
CO
non polar molecule
molecule where electrons are equally distributed, no localized charge
example of non polar molecule
CO2
water is a ___ molecule
polar
in a water molecule, the oxygen is a dipole negative charge, and the
hydrogen is dipole positive
a molecule can have polar covalent bonds but
still be non polar overall if the molecule is symmetrical
intramolecular forces are
forces WITHIN a single molecule (ionic and covalent bonds)
intermolecular forces are
BETWEEN two separate molecules (can der waal, dipole-dipole, london dispersion, hydrogen bonding)
intermolecular forces determine the
- physical state
- melting and boiling point
- surface tension
- solubility
there are no intermolecular forces in
ionic compounds (they don’t contain molecules)
ionic compounds don’t contain molecules, they contain
formula units
ionic bonds are generally very
strong
net dipole meaning
positive and negative end
polar molecules have a
net dipole
dipole-dipole force
intermolecular forces between oppositely charged ends of POLAR molecules
london dispersion force is a force acting between
ALL molecules, polar and non polar
the only intermolecular forces acting between non polar molecules are
london dispersion forces
london dispersion force is the result from a
very short-lived separation of charge, or temporary dipole that occurs from temporary electron density fluctuations
hydrogen bonds are
unusually strong dipole-dipole forces between positive hydrogen atoms and highly electronegative atoms
