Reaction Rates and Equilibrium Flashcards

Flashcards based on lecture notes about reaction rates and chemical equilibrium, covering collision theory, factors affecting reaction rates, and potential energy diagrams.

Electroplating Cell Electrolyte Concentration

The concentration of the electrolyte in an electroplating cell does not change because the metal lost at the anode is exactly replaced at the cathode, maintaining a constant concentration.

Reversible Reaction

A reaction where both the forward and reverse reactions occur simultaneously, leading to no observable change in concentrations.

Equilibrium

A state where the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products.

Collision Theory

For a reaction to occur, particles must collide with sufficient energy and correct orientation.

Effective Collision

A collision that occurs with enough energy and correct orientation, leading to a chemical reaction.

Factors Increasing Reaction Rate

Temperature, Concentration, Surface Area, and Pressure (for gases) increase the number of collisions and the likelihood of effective collisions, thus increasing the reaction rate.

Temperature Effect on Reaction Rate

Increasing temperature increases the average kinetic energy of particles, leading to more frequent and higher energy collisions.

Concentration Effect on Reaction Rate

Increasing concentration provides more particles available for collisions, thereby increasing the reaction rate.

Surface Area Effect on Reaction Rate

Increasing surface area exposes more particles of a reactant, making collisions more likely.

Pressure Effect on Reaction Rate (Gases)

Increasing pressure forces gas particles closer together, increasing the frequency of collisions.

Role of Catalysts

Catalysts increase reaction rates by providing an alternate reaction pathway with a lower activation energy; they are not consumed in the reaction.

Activated Complex

A high-energy intermediate state formed during a successful collision, representing the transition between reactants and products.

Potential Energy Diagram

A graphical representation showing the potential energy of reactants, products, and the activated complex during a reaction.

Activation Energy

The energy difference between the reactants and the activated complex; the minimum energy required for a reaction to occur.

Heat of Reaction (Enthalpy)

The energy difference between the reactants and the products (ΔH); negative for exothermic reactions, positive for endothermic reactions.

Catalyst Effect on Potential Energy Diagram

A catalyst lowers the energy of the activated complex, thereby reducing the activation energy required for the reaction.

Exothermic Reaction (Energy Diagram)

A reaction that releases energy (ΔH < 0), where the products have lower energy than the reactants.

Endothermic Reaction (Energy Diagram)

A reaction that absorbs energy (ΔH > 0), where the products have higher energy than the reactants.

Dynamic Equilibrium

State where the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products.