Energetics key words

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Across
  1. 8. The average value of the bond dissociation enthalpy for a given type of bond taken from a range of different compounds.
  2. 9. Describes a reaction in which heat energy is taken in from the surroundings – we experience a temperature drop.
  3. 10. The enthalpy change when 1 mole of a substance is completely burned in oxygen with all reactants and products in their standard states under standard conditions (298K and 100kPa).
  4. 11. An instrument for measuring the heat changes that accompany chemical reactions.
Down
  1. 1. The enthalpy change when 1 mole of substance is formed from it’s elements with all reactants and products in their standard states under standard conditions (298K and 100kPa).
  2. 2. Describes a reaction in which heat energy is given out by the chemical system – we experience a temperature rise.
  3. 3. change A measure of heat energy given out or taken in when a chemical or physical change occurs at constant pressure.
  4. 4. The amount of heat needed to raise the temperature of 1g of a substance by 1K.
  5. 5. A combustion reaction in which there is insufficient oxygen for all the carbon in the fuel to burn to carbon dioxide. Carbon monoxide and/or soot are formed.
  6. 6. A reaction in which water is added.
  7. 7. A sequence of chemical reactions (with their enthalpy changes) that convert a reactant into a product. The total enthalpy change of the sequence of reactions will be the same as that for the conversion of the reactant to the product directly (or by any other route).