1.5.1 Factors Affecting Reaction Rates

• What does the rate of chemical change measure?

  Reaction speed
• Order the reactions from slowest to fastest based on their rates:

  1️⃣ Rusting of iron

  2️⃣ Combustion of propane

  3️⃣ Neutralization of acid with base
• The frequency and energy of collisions between particles determine the speed of a chemical reaction


  True
• Match the reaction with its rate:

  Rusting of iron ↔️ Slow

  Combustion of propane ↔️ Fast

  Neutralization of acid with base ↔️ Very fast
• Higher temperatures increase reaction rates because more collisions achieve the necessary activation energy
• Why does powdered zinc react faster than a solid block of zinc?

  Larger surface area
• Powdered reactants have a much larger surface area compared to solid blocks.
• Which reaction has a slow rate?

  Rusting of iron
• Increasing the concentration of reactants leads to more frequent collisions and a faster reaction rate.


  True
• A larger surface area of reactants increases collision frequency and reaction rate.

  True
• What process relies on high pressure to increase the production of ammonia?

  Haber-Bosch process
• The rate of chemical change measures how quickly reactants are used up or products are formed over time
• What are the main factors affecting reaction rates?

  Temperature, concentration, surface area, catalysts
• What happens to the reaction rate when the temperature increases?

  Increases
• Increasing the concentration of reactants increases the frequency of collisions


  True
• A larger surface area leads to more frequent collisions and a faster reaction rate


  True
• Order the reactions from slowest to fastest based on their rates:

  1️⃣ Rusting of iron

  2️⃣ Combustion of propane

  3️⃣ Neutralization of acid with base
• Higher temperatures increase the kinetic energy of particles, leading to more frequent and energetic collisions.
• Higher temperatures increase the kinetic energy of reactant particles, causing them to move faster.
• What do catalysts provide to lower the activation energy of a reaction?

  Alternative reaction pathway
• What happens to the reaction rate when the concentration of reactants increases?

  Increases
• How does increasing temperature affect the kinetic energy of reactant particles?

  Increases it
• The rate of chemical change measures the speed at which reactants are used up or products are formed.

  True
• What happens to the reaction rate when the concentration of reactants is increased?

  Speeds up
• Reactions occur when particles collide with sufficient activation energy.


  True
• Higher temperatures increase the kinetic energy of reactant particles.


  True
• A larger surface area provides more sites for collisions to occur simultaneously.


  True
• Catalysts are consumed in the reaction process.

  False
• The collision theory states that reactions occur when particles collide with sufficient energy
• Catalysts lower the activation energy required for a reaction, making collisions more effective
• The rusting of iron is a fast chemical reaction

  False
• Catalysts increase reaction rates by providing an alternative pathway with lower energy
• Catalysts provide an alternative reaction pathway with lower activation energy
• What happens to the kinetic energy of particles when temperature increases?

  Increases
• What does collision theory state about collision frequency and reaction rate?

  More collisions, faster reaction
• The rate of chemical change measures the speed at which reactants are used up or products are formed over time.


  True
• How do catalysts affect reaction rates?

  Lower activation energy
• Order the collision frequency and reaction rate at different temperatures from lowest to highest.

  1️⃣ 25°C: Low collision frequency, slow reaction rate

  2️⃣ 50°C: Moderate collision frequency, moderate reaction rate

  3️⃣ 75°C: High collision frequency, fast reaction rate
• Increasing the pressure of a gas in a closed system compresses the gas, effectively increasing its concentration.
• According to the collision theory, reactions occur when reactant particles collide with sufficient energy