First Ionisation Energy
Is the energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions.
Is the repulsion between electrons in different inner shells. Shielding reduces the net attractive force from the positive nucleus on the outer-shell electrons.
Succesive Ionisation Energies
Are a measure of the energy required to remove each electron in turn.
Are a group of atomic orbitals with the same principal quantum number, n. Also known as a main energy level.
Principal Quantum Number
n, is a number representing the relative overall energy of each orbital, which increases with distance from the nucleus. The sets of orbitals with the same n-value are referred to as electron shells or energy levels.
Is a region within an atom that can hold up to two electrons with opposite spins.
Is a group of the same type of atomic orbitals (s,p, d or f) within a shell
Is the arrangement of electrons in an atom.
Are substances formed from two or more chemically bonded elements in a fixed ratio, usually shown by a chemical formula.
Is the electrostatic attraction between oppositely charged ions.
Giant Ionic Lattice
Is a three-dimensional structure of oppositely charged ions, held together by strong ionic bonds.
Are the vertical column in the periodic table. Elements in the same group have similar chemical properties and their atoms have the same number of outer-shell electrons.
Is a bond formed by a shared pair of electrons.
Is an outer-shell pair of electrons that is not involved in chemical bonding.
Is a measure of the attraction of a bonded atom for the pair of electrons in a covalent bond.
Is a small charge difference across a bond that results from a difference in the electronegativities of the bonded atoms.
Polar Covalent Bond
Has a permanent dipole
Is an attractive force between neighbouring molecules
Permanent Dipole-Dipole Force
Is a weak attractive force between permanent dipoles in neighbouring polar molecules
van der Waals' forces
Are attractive forces between induced dipoles in neighbouring molecules.
Is a strong dipole-dipole attraction between:
An electron-defcient hydrogen atom on one molecule and
A lone pair of electrons on a highly electronegative atom on a different molecule.
Is the electrostatic attraction between positive metal ions and delocalised electrons.
Are shared between more than two atoms
Giant Metallic Lattice
Is a three-dimensional structure of positive ions and delocalised electrons bonded together by strong metallic bonds.
Giant Covalent Lattice
Is a three-dimensional structure of atoms, bonded together by strong covalent bonds.