3. Chemical Bonding Flashcards
Ionic bonding
The electrostatic force of attraction between oppositely charged ions in an ionic crystal lattice
Covalent bonding
The force of attraction between a shared pair of electrons and the nuclei of the atoms
Co-ordinate (dative covalent) bonding
The bond formed when one atom donates one lone pair of electrons to another atom which has an empty orbital in its outer shell
Electronegativity
The ability of an atom to attract a bond pair of electrons towards itself in a covalent bond
Bond polarity
A polar bond is one in which the electron distribution is asymmetric, resulting in the two bonded atoms being partially charged
Dipole moment
The degree of polarity of a covalent bond in a molecule
Bond energy
The energy required to break one mole of a covalent bond between two atoms in the gaseous state
Bond length
The distance between the nuclei of two atoms joined by a covalent bond
Metallic bonding
The strong electrostatic force of attraction between positive metal ions and the sea of delocalised electrons
Explain, using ammonia as the example, the meaning of the term bond polarity. [2m]
- N and H have different electronegativity values
- N-H bond has a dipole / bonding pair is unequally shared
Explain why the ammonia molecule is polar. [2m]
- molecule is not symmetrical
- dipoles do not cancel out
At room temperature, iodine solid has a lattice structure.
Describe the arrangement of the iodine molecules within the solid. [1m]
Held in regular/uniform arrangement
