Chemistry (Bonding and Reactions) Flashcards
1
Q
Lewis Structures
A
Diagrams representing structure of atoms.
- Count total valence electrons (VE)
- Fill octets
2
Q
Formal charge
A
Method to determine whether a compound has a net charge on it and which atom is carrying the charge.
3
Q
Resonance Structures
A
Multiple possible Lewis Structures
- Bond connectivity
- Delocalized electrons
a. Stabilizes compound to become less reactive.
4
Q
Ionic Bonding
A
- Electrons transferred from one atom to another.
- Electronegativity difference (>1.7)
- Physical properties:
a. Very high melting and boiling point.
b. Liquid state conducts electricity.
5
Q
Covalent Bonding
A
- Electrons shared between atoms.
- Electronegativity difference (<1.7)
- Physical properties:
a. Melting + boiling points lower than ionic compounds.
6
Q
Bond order
A
- Single, longest, 1 sigma, weakest.
- Double, medium, 1 sigma + 1 pi, medium.
- Triple, shortest, 1 sigma + 2 pi, strongest.
7
Q
Polar covalent bond
A
- Electrons shared unequally among atoms.
- Electronegativity difference (0.4 to 1.7)
- Dipoles
a. p (dipole moment)= q (charge) * r (charge separation). - Physical properties:
a. Melting + boiling points lower than ionic but greater than non-polar compounds.
8
Q
Non-Polar Covalent bond
A
- Electrons shared equally between atoms.
- Electronegativity difference of elements (< 0.4)
a. diatomics: N2, O2
b. alkanes - Physical Properties:
a. Melting + boiling points lower than polar compounds.
9
Q
Coordinate Covalent Bond
A
- Electrons shared between atoms.
- Both electrons donated by one of the atoms.
- Physical properties:
a. hybridized characteristics of both ionic and Covalent compounds.
10
Q
London Dispersion Forces
A
- Weakest.
- Induced dipole.
- Size dependent.
a. More electrons makes it easier to polarize.
11
Q
Dipole-Dipole
A
- Medium.
- Polar molecules.
- Strongest in liquid and solid.
12
Q
Hydrogen Bonding
A
- Strongest.
2. H bonded to F, O and N.
13
Q
Linear
A
180° sp 2 bonds 0 lone pairs e.g CO2
14
Q
Trigonal Planar
A
120° sp2 3 bonds 0 lone pairs e.g CH2O
15
Q
Bent
A
104.5 ° sp3 2 bonds 1 or 2 lone pairs e.g H20