Energy/rates/equilibrium Flashcards
Exothermic reaction
Reaction that gives off energy into the surroundings
The value is negative (-)
Endothermic reaction
Takes in energy from the surroundings
The value is positive (+)
Enthalpy change
Overall Change in energy in KJ/mol
Specific heat capacity equation
Q = mc/_\T
Bond breaking is…
Endothermic
Bond forming is…
Exothermic
Enthalpy change =
Total energy absorbed to break bonds — total energy released in making bonds
Rate: temperature
Increases rate,
Particles have more energy so move faster which makes them have more frequent collisions
Rate: Increasing the concentration or pressure
It means there is more particles in the same volume so more likely collisions
For pressure the particles are more crowded so the collisions are more frequent
rate; Smaller surface area
Increased the surface area volume ratio with more solid exposed
The frequency of collisions will increase
Rate; catalyst
Increases the rate without being chemically changed or used
They decrease the activation energy and create an alternate path
Rates of reaction equation
Amount of reactant used or amount of product formed / time
Reversible reactions are
Reactions that can go forward and backwards and reform the reactants from the products
Dynamic equilibrium happens when
The reaction is in a closed system
It means the concentration of reactants and products will reach a balance
The reactions are happening at exactly the same rate so both reactions cancel each other out
Pressure effect on dynamic equilibrium
If you raise the pressure it favours the side with less moles of gas
If you reduce the pressure it will favour the side with more moles of gas
