Chemical Equilibrium Flashcards
What is dynamic equilibrium?
when the rate of the forward reaction is equal to the rate of the backward reaction
What can be said about the concentration of reactants and products?
they are constant but not equal
What is Le Chatelier’s principle?
any system at equilibrium will readjust itself to counteract any change applied
Temperature
- if temp is increased the equilibrium shifts to the exothermic end
- if temp is decreased the equilibrium shifts to the exothermic end
pressure
- if pressure increases the equilibrium shifts to the side with the lower number of moles
- if pressure decreases the equilibrium shifts to the side with the greater number of moles
What does the equilibrium constant give us an idea of?
the extent a reaction has gone to completion
What are standard conditions?
one mole of a substance at one atmosphere pressure and any specified temperature
What is the symbol for standard enthalpy?
ΔH
What is the equation for Gibbs Free energy?
ΔG=ΔH-TΔS
What is the enthalpy of formation?
the enthalpy change that occurs when one mole of a substance is formed from its elements in their standard states
How can the standard enthalpy of a reaction be calculated?
ΔH=ΔH(products)-ΔH(reactants)
What is entropy?
a measure of the disorder of a reaction
What is the relationship between entropy and temperature?
entropy increases with increased temperature
What is the entropy of a perfect water crystal at 0K?
zero
What is the second law of thermodynamics?
the total entropy of a reaction system and its surroundings always increases for a spontaneous change
