Electrons and Bonding Flashcards
What happens to energy as shell number increases?
Increases
What is the principal quantum number?
The shell number or energy level number
What is an atomic orbital?
A region around the nucleus that can hold up to two electrons, with opposite spins.
How many electrons can an orbital hold?
1 or 2
What are the 4 types of orbital?
S, P, D, F
What is the shape of the electron cloud of an S orbital?
Spherical
What happens to the shape of S orbital as there is a greater shell number?
The radius increases simultaneously
What is the shape of a P orbital? How are they orientated?
Dumb-bell shaped, there are 3 p-orbitals at right angles to each other
What happens to the p orbital as shell number increases?
The p orbital moves further away from the nucleus
How many orbitals do d and f orbitals have?
D=5
F=7
What do opposite spins help to counteract?
The repulsion between the negative charges of the two electrons
Define ‘ionic bonding’
The electrostatic attraction between positive and negative ions
What is the arrangement of a giant ionic lattice?
Ions surrounded by oppositely charged ions
What structure are ionic compounds at room temperature? Why?
Solids, insufficient energy to overcome strong electrostatic forces of attractions between oppositely charged ions
What are the boiling and melting points of ionic compounds like?
High, requires a large amount of energy to overcome strong electrostatic force of attraction between ions.
What 2 factors affect the boiling/melting points of ionic compounds?
Ionic Charge- greater= higher
Size of ions
What is the solubility of ionic compounds?
Depends on charge of ions. Low charges dissolve in polar solvents. Higher charges remain solid.
What two processes does solubility require?
Ionic Lattice must be broken down
Water molecules must attract and surround the atoms
When does an ionic compound conduct electricity?
When melted or dissolved in water
Define covalent bonding
Strong electrostatic attraction between a shared pair of electrons and the nuclei of bonded atoms
How does covalent bonding link to orbitals?
A covalent bond is the overalp of atomic orbitals, each containing an electron to give a shared pair of electrons
When can expansion of the octet occur?
From n=3 shell when the d sub-shell becomes available for expansion
What is a dative bond?
A covalent bond when the shared pair of electrons has been supplied by one of the bonding atoms only
What is the alternative name for a dative bond?
Coordinate bond
What is the measurement of covalent bond strength?
Average bond enthalpy
