Chapter 5 Electrons and Bonding Flashcards
What are shells?
Energy levels. Energy increases as the shell number increases. The shell number or energy level is called the principle quantum number n.
What are atomic orbitals?
A region around the nucleus that can hold up to 2 electrons with opposite spins. There is s, p, d and f orbitals.
What are the rules for filling of orbitals?
Orbitals fill in order of increasing energy.
Electrons pair with opposite spins
Orbitals with the same energy are occupied singly first, then pair up
What is ionic bonding?
The electrostatic attraction between positive and negative ions
What is the structure of ionic compounds?
Giant ionic lattice
What are the properties of ionic compounds?
HIgh melting and boiling points to overcome the strong electrostatic forces of attraction between oppositely charged ions.
Mostly soluble in polar solvents
Conduct electricity in aqueous or molten
What is covalent bonding?
Strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms, sharing a pair of electrons between the two atoms.
Where does covalent bonding occur?
Non-metallic elements
Polyatomic ions
What are the features of covalent bonds?
Overlap of atomic orbitals to give a shared pair of electrons
Attraction is localised
What are lone pairs?
Paired electrons that are not shared
What are multiple covalent bonds?
Exist when two atoms share more than one pair of electrons
What is dative covalent bonds?
A covalent bond in which the shared pair of electrons has been supplied by one of the bonding atoms only
