module 2

• Amount of a Substance (mole): A mole is the amount of substance containing as many particles as there

  are carbon atoms in exactly 12g of Carbon-12
• Avogadro constant, NA: The number of particles in one mole of any substance is equal to 6.02 x1023mol-1
• Molar Mass: The mass, in g, per mole of a substance, units = g mol-1
• Molar Gas Volume: The gas volume per mole of a substance. This is 24.0 dm3mol-1 at room temperature and pressure (RTP)
• Empirical Formula: The simplest whole number ratio of atoms of each element present in a compound
• Molecular Formula: The actual number and type of atoms of each element in a molecule
• Ideal Gas Equation: pV = nRT
• Hydrogen Bond: A strong dipole-dipole attraction between molecules containing O-H, N-H or F-H bonds
• Isotopes: Atoms of the same element (same number of protons and electrons) with different numbers of neutrons and different masses
• Relative Isotopic Mass: The mass of an atom of an isotope compared with 1/12 of the mass of an atom of Carbon-12
• Relative Atomic Mass: The weighted mean mass of an atom of an element compared with 1/12 of the mass of an atom of Carbon-12
• Atomic Orbital: A region around the nucleus that can hold up to two electrons, with opposite spins
• Anhydrous: When all the waters of crystallisation have been removed from a compound

  Hydrated: When water of crystallisation is present in a crystal compound

  Water of Crystallisation: The water present in a compound giving the compound a crystalline appearance.
• Percentage (%) Yield = __Actual mass of product__ x 100

  Theoretical mass of product

  Atom Economy = __Molecular mass of desired product__ x 100

  Molecular mass of ALL product
• Acid: Proton (H+) donor

  Base: Proton (H+) acceptor
• Alkali: A soluble base that dissolves in water to release OH- ions in aqueous solution
• Oxidation: The loss of electrons / increase in oxidation number (state)

  Reduction: The gain of electrons / decrease in oxidation number (state)
• Oxidising Agent: A reagent which oxidises another species (and is reduced itself) by gaining electrons

  Reducing Agent: A reagent which reduces another species (and is oxidised itself) by losing electrons
• Redox: A reaction where both oxidation and reduction takes place

  Disproportionation: A reaction in which the same element is both oxidised and reduced
• Metallic Bond: Strong electrostatic attraction between positively charged ions (cations) and delocalised electrons

  Ionic Bond: Strong electrostatic attraction between positive and negatively charged ions
• Covalent Bond: Electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms

  Dative (Co-ordinate) Covalent Bond: The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms, where only one of the atoms supplies both the electrons shared
• Electronegativity: The ability of an atom to attract the bonding electrons towards itself in a covalent bond