typesof solids Flashcards
metallic lattice particles
positive kernels and delocalised valance electrons
how do metallic lattices come about
result of metallic bonding
metallic lattice strength and strongness
strong
generally hard
metallic lattice bp and mp
high melting and boiling points as there are many strong electrostatic forces of attraction between positive kernels and delocalised valence electrons
metallic lattice malleability
Sheets of cations can slide past over each other but remain held together by electrostatic forces of attraction between positive kernels and delocalised valence electrons
Na vs Mg boiling point
more stronger electrostatic forces of attraction between positive kernels + delocalised electrons in Mg
cation of Mg is 2+ and cation of Na is 1+
Mg has higher boiling water
metallic lattice test for conductivity
have a system w a power supply, ammeter and apply potential difference across it
insert test substances between clips/ place substance in beaker using electrodes to make contact w substance
how do ionic lattices come about
result of ionic bonding
ionic lattice particles
anions + cations
strength ionic lattice
strong
ionic lattice mp+ bp
high
many strong electrostatic forces of attraction between cations and anions
more energy needed to overcome forces
Al2O3 vs NaF BP
electrostatic forces between Al3+ and O2- are stronger than those between Na+ and F- because the sizes of the charges are greater in Al2O3
therefore more energy is required to overcome the forces
brittle ionic solids
a shift in the arrangement of ions brings like charges alongside each other which result in a force of repulsion which causes the solid to fracture
ionic lattice test for conductivity
in solid state cations + anions are not free to move to carry charge in an ionic lattice. can melt solid- molten state or dissolve in water- aqueous state
molecular lattice particles
molecules held together by electrostatic forces (van der waals forces)
van der waals forces weakest to strongest
london forces
dipole-dipole forces of attraction
hydrogen bond forces
molecular lattice strength
weak
molecular lattice bp and mp
low
weak van der waals forces between molecules
less energy needed to overcome forces
molecular lattice conductivity
cannot conduct electric charge- neutral molecules
intramolecular bond
bond inside molecules (covalent bond)
intermolecular force
force between molecules
origin of london force
electrons randomly move around a molecule
at a point in times, electrons can exist more on 1 side of molecule forming a temporary dipole
when a temporary dipole comes close to a neighbouring, neutral molecule , this molecule polarises forming an induced dipole
the temporary and induced dipole electrostatically resulting in a london force
hydrogen bond force
when hydrogen is bonded to a small highly electronegative atom, ( N,O,F) w/ at least 1 lone pair, hydrogen bonding occurs
the highly electronegative atom pulls the pair of electrons towards itself exposing a naked proton
the naked proton electrostatically attracts the lone pair of the neighbouring molecule
phase change
intermolecular force overcome
chemical change
intramolecular bond broken
atomic lattice particles
atoms
diamond lattice strength
extremely strong , generally hard
diamond mp and bp
high
many strong,covalent bonds between atoms (4)
more energy required to break bonds
diamond conductivity
poor electrical conductor
no charges to move to carry charge (neutral atom)
graphite strength
extremely strong + hard
many strong covalent bonds between atoms (3 + 1unpaired e)
graphite mp + bp
high
many strong,covalent bonds between atoms (3)
more energy required to break bonds
graphite conductivity
good electrical conductor due to delocalised e-
silicon dioxide mp+ bp
high
many strong,covalent bonds between atoms (3)
more energy required to break bonds
silicon dioxide conductivity
poor conductor
no particles to move to carry charge (neutral atom)
