Bond Types
What are the three types of bonding and what types of elements are bonded in each type?
ionic - metal and nonmetal
covalent - nonmetal and nonmetal
metallic - metal and metal
What is the relationship between bond order, bond length, and bond strength?
As bond order increases, bond length decreases and bond strength increases.
Fill in the blanks: ____ compounds tend to be rigid, hard, and brittle. ____ compounds tend to be malleable, and molecular _____ compounds are soft, but hard as a solid compound
Ionic, metallic, and covalent
Lattice energy is relevant when looking at this type of bonding
Ionic bonding
What is the periodic trend for bond length and bond energy?
Bond length increases down a group in the periodic table and decreases across the period.
Bond energy shows the opposite trend.
Explain the bond length and strength between these three molecules
Explain the electrical conductivity of metallic, ionic, and covalent compounds
Metals are good conductors in solid and liquid states
Covalent compounds are not good conductors
Ionic compounds do not conduct electricity in the solid state, but can when they are melted or dissolved.
Define lattice energy
The energy released when 1 mole of ionic solid forms from its free ions in the gas phase
Rank the pairs of ions in order of increasing electrostatic potential energy: CaO, SrO, and MgO
SrO, CaO, MgO
Define bond energy (AKA bond enthalpy or bond strength)
The energy needed to overcome the attraction between the nuclei and the shared electrons in a covalent bond.
OR
The standard enthalpy change for breaking the bond in 1 mol of gaseous molecules
Describe the melting and boiling point trends of metallic compounds
Generally solids, metals typically have a high melting point and high boiling point because the cations and its valence electrons are very strongly attracted. Melting points of metals decrease down a group and increase across a period
What is the law pertaining to lattice energy of a compound?
Coulomb's law
What is electron pooling and when is it used?
In metallic bonds, involves the sea of electrons model that says the valence electrons of the metal atoms are delocalized and attract the cations and hold them together in an orderly array
If the overall change in energy of a compound is positive after breaking a covalent bond, what does that mean?
The bond breakage is endothermic, absorbs energy from the surroundings
Name the two types of covalent compounds and give a brief description of the difference between them
Molecular covalent compounds and network covalent solids
Molecular covalent compounds are individual molecules with strong intramolecular forces and weaker intermolecular forces, low melting and boiling points
Network covalent solids have no separate molecules, with strong intramolecular forces (bonds of atoms between different molecules), high melting points
Give one of the trends concerning lattice energy
Any of these:
As ionic size increases, lattice energy decreases
Decreases down a group on the periodic table
As ionic charge increases, lattice energy increases