Collision Theory/Factors of Rxn's
Potential Energy Diagrams
Equilibrium
Le Chatelier's Principle
Entropy
100
What are the three requirements of the collision theory?
1. Particles must collide
2. Proper orientation
3. Proper/Minimum amount of energy
100
Define an exothermic reaction.
Reactions that release energy/heat, -ΔH, energy is listed as product/on the right side
Reactants have more PE than the Products
100
Finish the following statement: Equilibrium occurs when...
the rate of the forward reaction EQUALS the rate of the reverse reaction.
100
Any change in temperature, concentration, or pressure is known as...
stress
100
What is entropy?
Degree of randomness or chaos or disorder or messiness in a system
200
Describe the relationship between the concentration of a solution and the rate of a reaction in terms of the collision theory.
As the concentration of a solution increases, the reaction rate increases due to more particles being present in the solution and a higher frequency/possibility of collisions.
200
The amount of energy lost or gained throughout a reaction is known as...
heat of reaction (ΔH)
200
What does the arrow look like in an equilibrium reaction?
↔
200
When there is a shift to the right, the rate of the forward reaction...
increases
200
Fill in the blank: Systems in nature tend to undergo changes toward __________ enthalpy and _____________ entropy.
lower and higher
300
What are the six factors that affect the rate of reaction?
Nature of reactants
Concentration
Pressure
Temperature
Surface area
Catalyst
300
If you reverse a reaction, then you must ___________ the sign for ΔH.
Reverse
300
Fill in the blank: In an equilibrium reaction, the concentrations of the reactants/products are ________.
Constant
300
Which way does the equilibrium shift when you add N2 (g)?
N2(g) + 3H2(g) ↔ 2NH3(g)
Shifts to the right.
300
As a substance changes from a solid to a gas, what happens to entropy?
It increases.
400
When a catalyst is added to a reaction, what does it change that results in the speeding up the rate of the reaction?
It lowers the activation energy
400
What letter represents the activated complex in this reaction? What letter is the activation energy of the forward reaction?
C
B
400
Fill in the blank: Phase equilibrium occurs during a ________________.
phase change
400
What happens to the concentration of H2 when you add NH3?
N2(g) + 3H2(g) ↔ 2NH3(g)
It increases.
400
When a compound breaks down, entropy...
increases
500
Given the balanced equation representing a reaction:
Mg(s) + 2HCl(aq) → H₂(g) + MgCl₂(aq)
Which set of reaction conditions produces H₂(g) at the fastest rate?
(1) 1.0-g lump of Mg(s) in 0.5 M HCl(aq) at 50.°C
(2) 1.0-g solid ribbon of Mg(s) in 0.5 M HCl(aq) at 40.°C
(3) 1.0 g of powdered Mg(s) in 1.0 M HCl(aq) at 50.°C
(4) 1.0 g of powdered Mg(s) in 1.0 M HCl(aq) at 40.°C
(3) 1.0 g of powdered Mg(s) in 1.0 M HCl(aq) at 50.°C
500
What is the ΔH for:
2Al2O3(s) → 4Al(s) + 3O2(g)
+3351 kJ
500
Equilibrium occurs at what type of saturation?
Saturated
500
What happens to the concentration of N2 when you increase pressure?
N2(g) + 3H2(g) ↔ 2NH3(g)
It decreases.
500
What happens to entropy in the following reaction:
4Al(s) + 3O2(g) → 2Al2O3(s)
It decreases