Energetics, Kinetics and Equilibrium Chemistry Flashcards
What is activation energy?
the minimum amount of energy needed to start a chemical reaction
Enthalpy change of combustion
the enthalpy change which occurs when one mole of the compound is burned completely under standard conditions
Enthalpy change of neutralization
the enthalpy change which occurs when an acid and alkali react together to form a mole of water under standard conditions
Enthalpy change of formation
the enthalpy change which occurs when one mole of the compound is formed under standard conditions
Enthalpy change of reaction
the enthalpy change which occurs when equation quantities of materials react under standard conditions
Effect of increasing or decreasing temperature on equilibrium
If temperature has increased, the equilibrium will shift in the direction of the endothermic reaction, as this will absorb the added heat and counteract the temperature increase.
If temperature has decreased, the equilibrium will shift in the direction of the exothermic reaction, as this will release heat and counteract the temperature decrease.
What is bond enthalpy?
the energy required to break one mole of the bonds in a substance in the gaseous state
What is the mean bond enthalpy?
the mean value of the bond enthalpy values for the X-Y bond averaged across a wide range of compounds
What is Hess’s Law?
The total enthalpy change in a chemical reaction is independent of the route by which the chemical reaction takes place as long as the initial and final conditions are the same
What is Dynamic Equilibrium?
When both the rates of the forward and backward reactions are equal to each other and the concentrations of reactants and products remain constant
Effect of increasing or decreasing pressure on equilibrium
Increasing pressure favors the side with fewer moles of gas so the equilibrium will shift to the side with less moles and the yield of less products will increase. Decreasing pressure favors the side with more moles so equilibrium will shift to the side of the reaction with more moles and its product yield will increase
Effect of increasing or decreasing concentration on equilibrium
