bonding and structure Flashcards
(18 cards)
What are the properties of ionic compounds
- hard, brittle crystalline substances
- high melting and boiling temperatures
- often soluble in water and polar solvents
- insoluble in non-polar solvents
- don’t conduct electricity when solid, only molten/aqueous
Define ionic bond
strong electrostatic attraction between two oppositely charged ions formed by electron transfer.
What happens to radii down a group?
- no. shells increase
- atomic radii increases
What is dative covalent bonding?
- the shared pair of electrons in a covalent bond come from only one of the bonding atoms.
what is electronegativity?
the ability of an atom to gain electrons towards itself
what is a dipole?
two charges within a molecule between two covalently bonded atoms or ions that share an ionic bond
what is debye
a unit of measurement to sow the electric dipole moment of a substance
what affects the polarity of a molecule?
the electronegativity of each atom
what are the type of intermolecular forces?
induced dipole forces
permanent dipole forces
hydrogen bonding
what are london forces?
weak intermolecular forces arising due to fluctuations of electron density within a nonpolar molecule
how does nuclear charge affect electronegativity?
higher nuclear charge means greater electronegativity as nucleus and outer electrons are more strongly attracted to each other
what is the trend in electronegativity across a period and why?
increases because there’s an increase in nuclear charge
what is the trend in electronegativity down a group and why?
decreases because there is more shielding of electrons
how does hydrogen bonding occur?
when a hydrogen atom is bonded to a highly electronegative atom
what affects the strength of permanent dipoles?
- difference in electronegativity
- larger difference means a stronger attraction of the permanent dipole
which elements are able to form hydrogen bonds
- oxygen
- nitrogen
-fluoride
which of the intermolecular bonds is the strongest?
hydrogen
