Class 12 Chemistry common misconceptions

Common NCERT Class 12 Chemistry misconceptions across 10 chapters, from Solutions to Biomolecules: the tempting mistake, why it feels right, and a worked visual example.

How to teach Class 12 Chemistry · Class 12 Chemistry questions with answers

• Chapter 1: Solutions

  Does molarity stay constant when a solution is warmed? — Tempting mistake: “The molarity remains unchanged because the amount of solute stays the same.”

  1 worked visual example · 8 “If your child says…” checks

• Chapter 2: Electrochemistry

  Does the anode always have a negative sign? — Tempting mistake: “Every anode is negative because the anode is negative in a galvanic cell.”

  1 worked visual example · 8 “If your child says…” checks

• Chapter 3: Chemical Kinetics

  Why are the rates for two reactants different? — Tempting mistake: “In 2A + B → products, A and B disappear at the same rate.”

  2 worked visual examples · 5 “If your child says…” checks

• Chapter 4: The d- and f-Block Elements

  Is every d-block element a transition element? — Tempting mistake: “Zinc is a transition element because it sits in the d block.”

  1 worked visual example · 6 “If your child says…” checks

• Chapter 5: Coordination Compounds

  Is coordination number the number of ligands? — Tempting mistake: “In [Co(en)₃]³⁺, the coordination number is 3 because there are three ligands.”

  1 worked visual example · 6 “If your child says…” checks

• Chapter 6: Haloalkanes and Haloarenes

  Should chlorobenzene react like chloroethane? — Tempting mistake: “Chlorobenzene readily substitutes chloride under the same conditions as chloroethane.”

  1 worked visual example · 6 “If your child says…” checks

• Chapter 7: Alcohols, Phenols and Ethers

  Is phenol as weak an acid as ethanol? — Tempting mistake: “Phenol and ethanol are equally acidic because both contain an –OH group.”

  1 worked visual example · 6 “If your child says…” checks

• Chapter 8: Aldehydes, Ketones and Carboxylic Acids

  Will every carbonyl compound give a silver mirror? — Tempting mistake: “Both ethanal and propanone give a positive Tollens test because both have C=O.”

  1 worked visual example · 6 “If your child says…” checks

• Chapter 9: Amines

  Do carbon atoms determine the amine class? — Tempting mistake: “Ethylamine is secondary because its ethyl group has two carbons.”

  1 worked visual example · 5 “If your child says…” checks

• Chapter 10: Biomolecules

  Is every disaccharide made with glucose reducing? — Tempting mistake: “Sucrose must be reducing because one of its units is glucose.”

  1 worked visual example · 6 “If your child says…” checks