IONIC BONDING
A. Concepts
1. The bond is the result of electron transfer.
2. A compound is formed when the number of positive and negative charges is equal.
3. formula unit- the simplest collection of atoms from which the ionic formula can be
established.
4. empirical formula- any chemical formula that shows the simplest whole number ratio
between atoms in a compound.
5. crystal lattice- an orderly arrangement of ions in an ionic compound that creates a three
dimensional structure.
6. lattice energy- energy released when one mole of an ionic crystal is formed from gaseous
ions.
B. Ionic Structures- varied shapes of points creating the lattice
1. cubic- three axes at right angles are of equal length.
2. tetragonal- three axes at right angles, two of equal length.
3. hexagonal- three equal axes at 60 degrees, vertical axes at right angle to these.
4. trigonal- three equal axes at non-right angles.
5. orthorhombic- three unequal axes at right angles.
6. monoclinic- three unequal axes, one is not a right angle.
7. triclinic- three unequal axes, all three non-right angles.
Ex. NaCl (cubic)