To:

Students in Singapore taking GCE ‘O’ Levels Chemistry Exams and using Marshall Cavendish’s Chemistry Matters as Reference Textbook

Besides the error on Electrolysis Topic that we have posted earlier, there is another error spotted in Organic Chemistry. It is shown on page 393 under “Test Yourself 22.1 – Worked Example”.

As we all know, Carbon (C) is found in Group IV of the Periodic Table and has 4 valence electrons. As such, the maximum number of covalent bonds that a carbon atom can formed is 4!

Zoom into Hydrocarbons B and you realised that the 2nd carbon atoms (counting from right side of structure) have:

1 C=C bond

1 C-C bond

2 C-H bond

This gives the 2nd carbon atom 5 covalent bonds which is incorrect. Please note. The correct structure should have only 1 C-H bond, rather than 2. In that way, you can solve the question which test you on Isomerism in Organic Chemistry.

Note:

Looking at the total number of covalent bonds for all the carbon atoms in an organic compound is the step you should take each time when you draw out the structural formula.

Thank you – if you are one of the two students that brought this out for our attention. We appreciate it! =)

PS: Leave us a comment on how you feel about this blogpost and it’s information. We would love to hear from you.

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• Chemistry Question – Intro to Organic Chemistry Part 1
• O Level Chemistry Question – Bonding & Structural Properties
• More Errors in Marshall Cavendish GCE ‘O’ Level “Chemistry Matters” Textbook – Part 3
• Difference between Atom, Molecule & Particle
• O Levels Chemistry Tips Blog Marathon – Day 4