Speed of Reaction Flashcards
What are 5 factors affecting speed of reaction?
- Temperature
- Concentration
- Pressure
- Surface area
- Catalyst
How does temperature affect speed of reaction?
At higher temperatures, reacting particles have MORE kinetic energy and move faster.
MORE reacting particles will have energy equal to or more than activation energy
Increased frequency of effective collisions between the reacting particles increases and rate of reaction increases
How does concentration affect rate of reaction?
A more concentrated solution contains MORE reacting particles per unit volume
Frequency of effective collision increases between the reacting particles, rate of reaction increases
How does pressure affect speed of reaction?
With smaller volume occupied by gas at higher pressure, number of reacting gas particles per unit volume increases
Gaseous particles are closer to each other,
Frequency of effective collisions between gas particles increases, hence rate of reaction increases
How does surface area affect speed of reaction?
The smaller the surface area (powdered), the larger the surface area (lumps/chips) of the same mass
Frequency of collisions, effective collisions between reacting particles increases, rate of reaction increases
How does presence of a catalyst affect speed of reaction?
Adding a catalyst provides an alternative pathway with lower activation energy
More reacting particles have energy greater or equal to activation energy
Frequency of effective collisions between reacting particles increases, hence rate of reaction increases
Types of catalyst
Transition metals
Platinum: Catalytic converter in car exhaust pipe
Nickel: Hydrogenation of alkenes
Iron: In Haber process for manufacture of ammonia
Transition metal oxides
Manganese(IV) oxide: decomposition of hydrogen peroxide
Vanadium(V) oxide: Contact process for making sulfuric acid
Enzymes
Enzymes in yeast: Fermentation of sugar to produce ethanol
Proteases: Breaking down proteins in baby food production
