Physical Chapter 5: Kinetics, Equilibria, and Redox Flashcards
What is reaction rate defined as?
The amount of reactant used or product formed over time
What is Collision theory?
The idea that particles have to collide with a sufficient amount of kinetic energy in order to react
What is Activation energy?
The minimum amount of energy needed for particles to react
What is the Maxwell-Boltsman distribution?
A graph showing the distribution of molecules at certain energy levels
What does the area under the Maxwell-Boltsman curve represent?
The total number of molecules
What is the effect of increasing temperature on reaction rate?
Rate will increase
Why does increasing temperature increase rate of reaction?
Each molecule will have greater energy and therefore more will meet the activation energy.
What is the effect of increased concentration on rate of reaction?
It will increase the rate
What is the effect of increased pressure on rate of reaction?
It will increase the rate
What is the effect of a catalyst on rate of reaction?
It provides an alternate pathway for the reaction with a loer activation energy - rate will increase
What are the three main ways to measure reaction rates?
Time taken for a precipitate to form
Measuring a decrease in mass
Measuring volume of gas given off
What is a reversible reaction?
A reaction that can go either way
What is dynamic equilibrium?
All products and reactants’ concentrations stay constant
What is Le Chatelier’s principle?
If a reaction at equilibirum is subjected to a change, the position of equilibrium will move to counter that change.
What is Le Chatelier’s principle?
If a reaction at equilibirum is subjected to a change, the position of equilibrium will move to counter that change.
What is Le Chatelier’s principle?
If a reaction at equilibirum is subjected to a change, the position of equilibrium will move to counter that change.
What will happen if you increase the temperature of an equilibrium mixture?
The position of Equilibrium will move in the endothermic direction
What will happen if you increase the concentration of a product in an equilibrium mixture?
The position of equilibrium will move to the left to produce more reactant
What will happen if you increase the pressure of an equilbrium mixture?
The position of equilbrium will move towards the side with less molecules
What effect do catalysts have on position of equilibrium?
None
What affects how reaction conditions are chosen in industry?
Compromise between speed, yield, and cost of production
What is the Equilibrium constant written as?
Kc
What is the formula for Kc?
Where aA + bB <-> cC + dD,
Kc = [D]d[C]c/[A]a[B]b
What is the only factor that affects Kc?
Temperature
How does temperature affect Kc?
If it means there is more product at equilibrium, Kc will rise. If it means less product at Equilibrium, Kc will fall.
What is the definition of a redox reaction?
Any reaction where electrons are transferred
What is oxidation?
Loss of electrons
What is reduction?
Gain of electrons
What is an oxidising agent?
A chemical that gets reduced
What is a reducing agent?
A chemical that gets oxidised
How do you assign oxidation states?
Overall oxidation state is equal to the charge of the ion or compound
Oxidation state of each element is often the same as the charge on its ion (e.g. O will often be 2-)
How do you combine half-equations?
Make sure the charges & electrons match
