Testing Relative Oxidizing and Reducing Strengths of Metal Atoms
Metal atoms with low ionization energies and non-metal atoms with high electron affinity form...
-
Upload
isaac-brown -
Category
Documents
-
view
230 -
download
3
Transcript of Metal atoms with low ionization energies and non-metal atoms with high electron affinity form...
• Metal atoms with low ionization energies and non-metal atoms with high electron affinity form cations (+) and anions (-)
• Oppositely charged ions attract to a crystalline structure
Ionic Bonding
Lattice Energy
Quantity of energy required for 1 mole of the solid ionic substance to be separated into its ions
Higher – more stable Very high in ionic substances This accounts for high melting temp., and hard
and brittle nature
Process of Ionic Bond Formation
Always exothermic Compound forms because it is more stable
(lower in energy) than its elements Stability comes from packing of ions together Lattice energy increases as the charges on
ions increase and radii decrease
Ionic Structures
Can have many types of arrangements Arrangement depends on the charge and size
of the ions involved
• Which substance would have a higher lattice energy : NaF or MgO?
• Which would have a higher lattice energy: FeO or Fe2O3?
Forming The Ions
The ions are formed when electrons are transferred from the atom with low electronegativity to an atom with high electronegativity
Predict the compound formed between aluminum and fluorine.
Transition-Metal Ions
Transition metals form many differently charged ions (some 2+, some 1+, some 3+)
In forming ions the transition metals lose the s electrons first and then as many d electrons as necessary to form the ion of that particular charge
Sizes of Ions
Cations are smaller than their parents Anions are larger than their parents Ions of the same charge, size increases going
down a group List the following in order of decreasing size
Mg2+, Ca2+, Ca
Isoelectric Series
Comparitive sizes of ions all possessing the same number of electrons
As nuclear charge increases, the radius decreases
O2- > F- > Na+ > Mg2+ > Al3+