BONDING Flashcards
Ionic bonidng occurs betwen which types of elements?
metals and non-metals
what type of elements loses electrons
metals
what type of elements gains electrons
non- metals
describe:
ionic bonding
structure
Physical properties
giant ionic lattice
strong ionic bonding
high melting and boiling points strong electrostatic forces of attraction between oppositely charged ions
Don’t conduct electricity as solid as ions are fixed positions
conduct electricity as liquids as ions are free to move
describe
metallic bonding
structure
properties
metallic bonding
giant metallic lattice
high melting point as strong electrostatic forces of attraction between + ions and delocalised e- require lots of energy to overcome
Macro molecular structure
covalent bond between atoms
macromolecular bonding
high melting and boiling point as strong covalent bond between atoms the structure requires a lot of energy to overcome
don’t conduct electricity except graphite
Diamond: no moving charges
graphite: delocalised e- layers can slide over each other
simple molecular structure
strong covalent bond between atoms
weak intermolecular forces between molecules
low melting and boiling point as intermolecular forces between the molecules are weak
don’t conduct electricity as molecules are neutral so there are no moving charges electrons are localised in the bonds
comparing metal atoms between x and y model answer
x has a greater charge of ….+
x has twice as many electrons in the sea of delocalised e-
x ions are smaller , meaning there is a greater density
therefore the attraction between x ions and delocalised e- is stronger
importance of hydrogen boning
Ice: less dense then water because hydrogen bonds in ice hold the molecule further apart
how does induced dipole diple arise
random movement of e- in one molecule leads an uneven distribution of e- , creating a temporary dipole in one molecule. This induces a dipole in the other molecule. dipoles attract
how does permanent dipole dipole forces arrise?
difference in electronegativity leads to bond polarity
dipole don’t cancel therefor the molecule has an overall permanent dipole
there is an attraction between delta positive on one molecule and delta negative on an other
how does hydrogen bonding arrise
large difference in electronegativity between NOF and hydrogen
creates a dipole on NOF-H bond
ions pair on NOF atom in one molecule strongly attracts a partially positive hydrogen atom on a different molecule
Coordinate bonds
definition: shared e- pair which both comes from the same atom
Properties: act as a covalent bond
Valence shell e- par repulsion theory
minimise their repulsion the e- pair repeal each other as far apart as possible
lone pair to lone pair >lone pair to bonding pair> bonding pair to bonding pair
electronegativity definition
power of an atom to attract the pair of e- in a covalent bond