Bonding Flashcards
when do ions form?
ions form when electrons are transferred between elements that have a large difference in electronegativity
what forces hold a lattice together?
strong electrostatic forces
describe and explain the melting point of ionic structures?
very high melting point due to strong electrostatic forces between oppositely charged ions. they require a lot of energy to break
how are ionic structures generally soluble in water?
water is polar. it contains lots of h bonds that can disrupt the electrostatic forces between the ions and break them up.
how are ionic structures electrical insulators when solid?
ions are in a fixed position, so are unable to carry an electrical charge.
how are ionic structures electrical conductors?
when molten or dissolved, the ions are free to move, so are able to carry a charge.
why are ionic structures brittle?
when ions are moved, they no longer have an alternating arrangement. this means they repel each other and the lattice breaks.
what is an ionic structure sometimes referred to as?
a lattice.
what are the 5 properties of ionic structures?
. high melting point
. electrical insulators when solid
. conduct electricity when
molten or dissolved
. generally soluble in water
. brittle
what is a covalent bond?
a shared pair of electrons with opposite spins. one electron is donated by each atom.
how do covalent bonds form?
they form between elements with high electronegativity values (i.e. non-metals)
what are the forces involved in electrostatic forces?
strong electrostatic forces between the positive nucleus and negative electrons.
what are the 2 structures of covalent bonds?
. molecular / simple molecular
. macromolecular / giant
covalent
examples of a macromolecules?
diamond and graphite
what is the bonding angle and electron pairs of Linear shapes
2 bonding pairs 0 lone pairs
180 degree angle
