Topic 9 - KINETICS I
No description yet. This curated deck is ready for daily study.
Card preview (16)
What is the effect of increased concentration on rate?
• More reactant particles per unit volume • More frequent collisions • More successful collisions per unit time • Rate increases
What is the effect of increased gas pressure on rate?
• More reactant molecules per unit area • More frequent collisions • More successful collisions per unit time • Rate increases
What is the effect of increased temperature on rate?
• Molecules have more kinetic energy • Greater proportion of collisions with energy greater than the activation energy • Rate increases
What is the definition of activation energy?
The minimum energy required for a collision to be successful
What is the effect of a catalyst on reaction rate?
• Provides a lower energy pathway • Decreases the activation energy • Rate increases
How does the shape of the Maxwell-Boltzmann distribution curve change as temperature increases?
The peak decreases in height and moves to the right
What is manufactured when hydrogen is added in the presence of a nickel catalyst?
Margarine
What is the catalyst required in cracking?
Aluminium oxide/Silica
What is the catalyst required in the manufacturing of margarine?
Nickel
What is the catalyst required in the haber process?
Solid iron
Definition of adsorption
A process in which atoms, molecules or ions are held on the surface of a solid
Definition of a catalyst
Alters the rate of a chemical reaction without permanently changing chemically
Definition of desorption
Removal of an adsorbed molecules, atom or ion from an adsorbent
What is catalyst poisoning?
When other substances adsorb to the surface of the catalyst, blocking the active site
Outline the stages that allow H2 to react with CO2 in the presence of a solid catalyst (PPQ)
• Adsorption of H2 onto surface • Bonds are weakened • Desorption of products
The heterogenous catalyst palladium was suggested for use in this reaction. Explain how impurities in the gaseous reactants could make the catalyst less effective (PPQ)
• Impurities are adsorbed, blocking the active site • Impurities prevent bond weakening • Impurities form strong bonds to the surface