State how ions form and why they attract each other
What’s ionic bonding
Bonding that involves electrostatic attraction between oppositely charged ions in a lattice
Formula of sulfate ion
SO₄²-
Formula of hydroxide ion
OH¯
Formula of nitrate ion
NO3-
Formula of carbonate ion
HCO3-
Formula of ammonium ion
NH₄⁺
State the properties of ionically bonded compounds
-Always solids at room temperature > have giant structures and therefore high melting temperatures > in order to melt an ionic compound, a lot of energy is required to break up the lattice of ions
Describe the structure of ionically bonded compounds
The structure of this ionic compound is a giant lattice with oppositely charged ions and strong electrostatic forces (attractive forces between ions) between them
Describe a covalent bond
Describe a co-ordinate bond (dative covalent)
Describe the properties of covalently bonded molecules
Define electronegativity
measure of tendency of an atom to attract a bonding pair of electrons in a covalent bond
-greater the e.n. of an atom the more it attracts electrons towards it
Factors that affect electronegativity of an atom
-atomic charge
-distance from nucleus (atomic nucleus)
-electron sheilding
Non-polar covalent bonds
no difference between electronegativities e.g. Cl-Cl
-symmetrical molecules are non-polar even though they contain polar bonds
Polar covalent bonds
Small difference between electronegativities e.g. H-Cl
Ionic bond
Large difference in electronegativities
Difference between intermolecular and intramolecular forces
Intermolecular - attractive forces between neighbouring molecules
intramolecular -bonds that act WITHIN one molecule
Linear shape
Linear Shape (2)
Trigonal Planar
V-shaped/ bend/ non linear
Tetrahedral
-4 electron pairs
-4 bonding pairs
-0 lone pairs
-109.5
-e.g. CH4
Triangular pyramid
-4 electron pairs
-3 bonding pairs
-1 lone pair
-107
-e.g. NH3