Bonding (All 3) Flashcards
Define Metallic bonding (Mg, Na, Cu)
between metals
strong electrostatic attraction between positive metal ions and delocalised electrons
Define Ionic bonding (NaCl, CaCO3)
between a metal and non metal
strong electrostatic attraction between positive and negative ions
Simple Molecular (F2, CH4, Ne, SO3) has
Covalent bonds between ATOMS but IMFS between MOLECULES.
Covalent bond
shared pair of electrons between 2 non metals
Relative Strengths of bonding
(strongest) covalent > metallic > ionic > IMF’s (weakest)
Coordinate bond (always represented by an arrow)
shared electron pair which have been donated from the same atom
Strengths of repulsion
(strongest) lone pair - lone pair > lone pair - bonding pair > bonding pair - bonding pair (weakest)
Define Electronegativity
Ability to attract the pair of electrons in a covalent bond.
How to work out if a molecule is polar
- Unsymmetrical (doesn’t stay the same around central atom)
- dipoles do not cancel out
POLAR
How to work out if a molecule is Non - polar
- symmetrical (stays same all around central atom)
- dipoles cancel out
NON - POLAR
How to work out the type of IMF a molecule will have
does the molecule have O-H, N-H, F-H bonds?
Yes = Hydrogen bonding.
no = check if the molecule is polar?
yes= permanent dipole dipole forces between molecules
no = van der waals forces between molecules.
How and when does hydrogen bonding occur?
occurs between H atom bonded to O/N/F and a lone pair on O/N/F on another molecule.
arises if there is
- large difference in electronegativity
- strong attraction between lone pair of oxygen atoms and partially positive hydrogen atom on another molecule.
How and when does permanent dipole dipole forces occur?
occurs between polar molecules
arises when:
- difference in electronegativity
- attraction between the partial positive hydrogen atom and a partially negative chlorine on another atom.
How and when does van der waals forces occur?
occurs between all molecules
arises when:
- movement of electrons causes uneven distribution.
- which induces a dipole on another molecule
- attraction between dipoles of neighbouring molecules.
2 bonding, 0 lone
Linear, 180
