Term
| Entahlpy change of formation |
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Definition
| This is where one mole of product is formed from its constiuent elements in their standard states under standard conditions of 298K and 100KPa. |
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Term
| Enthalpy change of combustion |
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Definition
| The enthalpy change that takes place when one mole of a substance reacts fully with oxygen under standard conditions with all reactants and products in their standard states. |
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Term
| Enthalpy change of reaction |
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Definition
| The enthalpy change that goes with a reaction in the molar quantities under standard conditions with reactants and products in standard states |
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Term
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Definition
| A pressure of 100KPa a stated temperature, usually 298K and a concentration of 1 mole per dm -3 |
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Term
| the Boltzmann Distibution |
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Definition
| The distribution of energies of molecules at a particular temperature, usually shown as a graph |
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Term
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Definition
| The heat content that is stored in a chemical system |
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Term
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Definition
| A reaction in which the enthalpy of products is smaller than that of the reactants, resulting in a heat loss |
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Definition
| A reaction in which the enthalpy of the products is greater than the enthalpy of reactants, resulting in a heat gain. |
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Term
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Definition
| A diagram for a reaction to compare the enthalpy of the reactants with the enthalpy of the products |
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Term
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Definition
| The minimum energy required to start a reaction by the breaking of bonds |
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Term
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Definition
| the physical state of a substance under the standard conditions, 298K and 100KPa |
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Term
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Definition
| The energy required to raise the temperature of 1g of a substance by 1C |
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Term
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Definition
| the enthalpy change that takes place when breaking by homolytic fission 1 mole of a given bond in the molecules of a gaseous species |
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Term
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Definition
| the average enthalpy change that takes place when breaking homolytic fission 1 mole of a given type of bond in the molecules of a gaseous species. |
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Term
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Definition
| if a reaction can take place by more than one route and the intial and final conditions are the same, the total enthalpy change is the same for each route |
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Term
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Definition
| a diagram showing alternative routes between reactants and products that allows the indirect determination of an enthalpy change from other known enthalpy changes using Hess's Law |
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Term
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Definition
| the change in concentration of a reactant or product over time |
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Term
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Definition
| a reaction in which the catalyst has a different physical state from the reactants; frequently, reactants are gases whilst the catalyst is a solid |
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Term
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Definition
| a reaction in which the catalyst and reactants are in the same physical state, which is most frequently the aqueous or gaseous state |
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Term
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Definition
| when a system in dynamic equilibrium is subjected to a change, the position of equilibrium will shift to minimise the change |
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Term
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Definition
| the equilibrium that exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction |
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