Chemical Reactions and Electrolysis
The third page of this OCR GCSE Chemistry revision guide focuses on chemical reactions, with a particular emphasis on electrolysis and acid-base reactions. This section is crucial for students preparing for OCR GCSE Chemistry Questions by topic.
Definition: Electrolysis is the process by which ionic substances are decomposed into simpler substances when an electric current is passed through them.
The guide explains the process of electroplating, a practical application of electrolysis used in industry. It also covers the concept of reduction, which is central to understanding electrolysis reactions.
Example: In the reduction of copper ions, Cu²⁺(aq) + 2e⁻ → Cu(s), the copper ions gain electrons to form copper metal.
The page introduces the pH scale and discusses acid-base reactions, including neutralization. These concepts are fundamental in GCSE Chemistry and often appear in exam questions.
Vocabulary: Neutralization is a chemical reaction in which an acid and a base react quantitatively with each other to form a salt and water.
The guide also covers reaction profiles, which help students visualize the energy changes that occur during chemical reactions. It introduces the concept of activation energy, which is crucial for understanding reaction rates.
Highlight: The law of conservation of mass states that atoms are neither created nor destroyed in chemical reactions. This is why balanced symbol equations have the same number of atoms of each element on both sides.
This section provides essential knowledge for students studying OCR Chemistry GCSE and prepares them for questions on chemical reactions and electrolysis in their exams. It also reinforces the importance of balancing equations and understanding energy changes in reactions.
