Measuring the Rate of a Reaction Reaction rate The rate of reaction is the speed at which a chemical reaction takes place and has units mol dm-3 s-1 or mol dm-3 min-1 The rate of a reaction ...
Bond Enthalpies The amount of energy required to break one mole of a specific covalent bond in the gas phase is called the bond dissociation energy Bond dissociation energy (E) is usually ju...
Hess' Law Calculations You must make sure that you can apply Hess' Law effectively and calculate enthalpy changes in different situations Remember - it is the data that is important Check wh...
Using Hess' Law Calculating ΔHr from ΔHf using Hess’s Law energy cycles The products can be directly formed from the elements = ΔH2 OR The products can be indirectly formed from the elements...
Calorimetry Measuring enthalpy changes Calorimetry is the measurement enthalpy changes in chemical reactions A simple calorimeter can be made from a polystyrene drinking cup, a vacuum flask ...
Enthalpy Changes The total chemical energy inside a substance is called the enthalpy (or heat content) When chemical reactions take place, changes in chemical energy take place and therefore...
Energy Level Diagrams An energy level diagram is a diagram that shows the energies of the reactants, the transition state(s) and the products of the reaction as the reaction proceeds ( calle...
Influence of Intermolecular Forces Properties of water Hydrogen bonding in water, causes it to have anomalous properties such as high melting and boiling points, high surface tension and a h...
Intramolecular Forces vs. Intermolecular Forces Intramolecular forces Intramolecular forces are forces within a molecule and are usually covalent bonds Covalent bonds are formed when the out...
