Rates Of Reaction
Overview
Some reactions happen in an instant - an explosion takes milliseconds. Others take years - iron rusts slowly in damp air. Understanding what controls the speed of a reaction lets chemists speed up useful processes and slow down harmful ones.
In this lesson you will learn how surface area, concentration, temperature, pressure, and catalysts affect the rate of reaction, all explained through collision theory. You will also explore the classic marble chips practical.
Objectives
- Describe experiments to investigate the effects of changes in surface area of a solid, concentration of a solution, temperature and the use of a catalyst on the rate of a reaction
- Describe the effects of changes in surface area of a solid, concentration of a solution, pressure of a gas, temperature and the use of a catalyst on the rate of a reaction
- Know that a catalyst is a substance that increases the rate of a reaction but is chemically unchanged at the end of the reaction
- Investigate the effect of changing the surface area of marble chips and of changing the concentration of hydrochloric acid on the rate of reaction between marble chips and dilute hydrochloric acid
Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Rates Of Reaction. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- According to collision theory, a reaction occurs when particles: A) Touch each other B) Collide with sufficient energy C) Are heated to 100 degrees C D) Are in the same container Answer: B
- Which factor does NOT affect the rate of reaction? A) Temperature B) Surface area C) Colour of reactant D) Concentration Answer: C
- A catalyst works by: A) Increasing the temperature B) Providing a pathway with lower activation energy C) Increasing the concentration D) Being used up in the reaction Answer: B
- Grinding a solid into powder increases the rate because it: A) Increases the activation energy B) Increases the surface area C) Changes the products D) Acts as a catalyst Answer: B
- On a graph of gas volume vs time, a steeper line means: A) A slower reaction B) A faster reaction C) More products formed D) A higher temperature Answer: B
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Practice Mock Questions
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