Dear GCE ‘O’ Level (as well as IP) students using Marshall Cavendish Chemistry Textbook as reference text,
Please note that there is a printing error in the chemistry textbook (third impression 2008) that many of you did not realised (just like many of my students, until recently).
The error in print is on Page 271 under the Chapter of “Electrolysis” in Chemistry Matters for Pure Chemistry syllabus.
In the Key Ideas which acts like sub-section summary, it states that “OH- ions will be discharged as oxygen gas. However, if a solution is concentrated in halide ions, the halogen gas will be produced.” – At The Cathode! This is certainly not true as we know that The Cathode in an electrolytic cell is always negative charged and Cations (+ve ions) are attracted towards it and will be selectively discharged.
At the anode which is positively charged, Anions (-ve ions) will be attracted to it and be selectively discharged. As such, the information that “H+ ions will be discharged…..” is also incorrect in the Key Ideas.
In view that many of you rely alot on the Key Ideas for summarising the chapter, please take note of this glitch when you are revising for your GCE ‘O’ Level Chemistry Examinations.
Hope this information helps.
PS: If you know of anymore errors in print in this textbook (or other chemistry textbook), feel free to share your information here. Readers (mostly students and educators) will be grateful to you.
PPS: We would certainly love to here from you on this!
Updates on 17th Oct: There is another error in the book on Organic Chemistry. Click here to find out!
- O Level Chemistry – Products of Electrolysis of Molten Compound
- O-Level Chemistry: Question on Electrolysis & Mole Calculations
- O Level Chemistry – Definitions of Electrolysis
- More Error in Marshall Cavendish GCE ‘O’ Level “Chemistry Matters” Textbook – Part 2
- O Level Chemistry: Challenging Mole Calculation / Electrolysis Questions