Unit 1 - Bonding & Structure Flashcards
where does metallic bonding occur?
between the atoms of metal elements
what is metallic bonding?
the attraction of the positively charged ions for the delocalised electrons.
how do metals exist?
as a giant lattice of positive ions held together by delocalised electrons.
how can a metal be identified?
they conduct electricity
what is responsible for metals being able to conduct electricity?
the delocaslised sea of electrons
what are discrete covalent molecules?
small groups of atoms held together by strong covalent bonds inside the molecule and weak intermolecular forces between the molecules.
what is a covalent bond?
a shared pair of electrons electrostatically attracted to the positive nuclei of two non-metal atoms.
give 3 examples of larger covalent molecular elements
phosphorus
sulfur
fullerenes
what are most of the discrete covalent molecules?
diatomic elements
what are covalent networks?
large, rigid three-dimensional arrangements of atoms held together by strong covalent bonds
why do covalent networks have high melting points?
they only contain strong bonds.
2 examples of covalent networks?
diamond and graphite
what are monotomic elements?
elements that exist as single, unattached particles.
what is bonding inside molecules called?
intramolecular bonds
what is bonding between molecules called?
intermolecular bonds
where do pure covalent bonds exist?
between two atoms with the same electronegativities.
how much ionic character does a pure covalent bond have?
none.
what are good examples of pure covalent bonds?
diatomic elements
what is a polar covalent bond?
a bond formed when a shared pair of electrons is not shared equally.
where are ionic bonds mostly formed?
between a metal and non-metal with a large difference in electronegativity.
what is an ionic bond?
the electrostatic force of attraction between a metal ion and a non-metal ion
what are ions arranged into?
a 3-dimensional ionic lattice
how is the type of bonding in a compound determined?
by the differences in electronegativity between the elements involved.
what type of bonding is present between elements with the same electronegativities?
pure covalent
what type of bonding is present between elements with a differenece in electronegativity greater than or equal to 2?
ionic bonding
what type pf bonding is present between elements with a difference in electronegativity which is less than 2?
polar covalent
where do London Dispersion forces exist?
between all atoms and molecules
what affects the strength of London Dispersion forces?
the size of the molecule or atom
what happens to London Dispersion forces as atomic size increases?
they increase
are molecules with a permanent dipole polar or non polar?
polar
what is the strongest type of intermolecular bond?
Hydrogen bonds
