Rate of Reactions
1. Factors Affecting Reaction Rates
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🔹 Concentration and Pressure:
Increasing concentration or pressure increases reaction rate by causing more frequent collisions.
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🔹 Particle Size:
Smaller particle size increases surface area, speeding up reactions.
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🔹 Temperature:
Higher temperature increases kinetic energy, leading to more successful collisions and faster reactions.
2. Catalysts
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🔹 Definition:
Catalysts speed up reactions without being consumed.
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🔹 Enzymes:
Biological catalysts that increase reaction rates in living organisms.
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🔹 Activation Energy:
Catalysts lower the activation energy needed, allowing reactions to proceed faster.
3. Industrial Catalysts
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🔹 Description:
Certain compounds act as catalysts in industries to increase efficiency and reduce costs.
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🔹 Example:
Haber process uses catalysts to synthesize ammonia.
4. Investigating Reaction Rates
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🔹 Experimental Variables:
Vary concentration, pressure, temperature, particle size, or catalyst presence to measure effects on rate.
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🔹 Data Interpretation:
Analyze changes in reaction time, product formation, or reactant disappearance to determine rate effects.
- ⚠️ Catalysts are used up during the reaction; actually, catalysts remain unchanged.
- ⚠️ Increasing concentration always increases reaction rate linearly; the relationship may vary depending on reaction order.
- ⚠️ Temperature only affects reaction speed; it also affects the energy distribution of particles.
- 👉 Explain how each factor affects reaction rate using collision theory.
- 👉 Describe the role and benefits of catalysts in both biological and industrial contexts.
- 👉 Outline experimental setups to investigate factors affecting reaction rates.
- 👉 Practice interpreting graphs showing reactant concentration or product formation over time.