In-text Questions — Ethanol and Ethanoic Acid — Carbon and its Compounds

1. 12 marksNCERT Cl-10 Science, In-text Qs after §4.4.2, Q1

   How would you distinguish experimentally between an alcohol and a carboxylic acid?

   Hint. Think of a reagent that reacts with one of these functional groups but not the other, producing something you can visibly see or test for.

   Step 1 — Choose a suitable test reagent. Sodium hydrogencarbonate (baking soda) reacts with carboxylic acids but not with alcohols.

   Step 2 — Describe what happens with each. Adding the sample to sodium hydrogencarbonate solution: a carboxylic acid produces brisk effervescence of carbon dioxide gas (which turns limewater milky), since the acid reacts with the hydrogencarbonate, while an alcohol shows no reaction at all — no bubbling.

   ✦ Answer: Add sodium hydrogencarbonate solution to each sample — a carboxylic acid fizzes vigorously (releasing CO₂, confirmed by turning limewater milky), while an alcohol shows no reaction.

   Where students slip. Relying only on litmus paper — while a carboxylic acid does turn blue litmus red and alcohol doesn't, the effervescence test with sodium hydrogencarbonate is the more decisive, unambiguous distinguishing test.

2. 21 markNCERT Cl-10 Science, In-text Qs after §4.4.2, Q2

   What are oxidising agents?

   Hint. This is directly named right after the alcohol-to-acid oxidation reaction earlier in the chapter.

   Step 1 — Define the term. Oxidising agents are substances capable of adding oxygen to another substance, oxidising it.

   Step 2 — Give examples from the chapter. Alkaline potassium permanganate and acidified potassium dichromate are both oxidising agents, since they add oxygen when converting alcohols to carboxylic acids.

   ✦ Answer: Substances that add oxygen to another substance during a reaction — e.g. alkaline KMnO₄ and acidified K₂Cr₂O₇.

   Where students slip. Describing oxidising agents as substances that 'get oxidised' — it's the other way around: an oxidising agent supplies oxygen to (oxidises) something else, and in doing so is itself typically reduced.

Solutions written by the tuition.in editorial team and checked against the NCERT Class 10 Science textbook, Reprint 2026-27 (jesc104.pdf) — five in-text question sets (13 questions total, not 18 as some older manifests claim) plus one end-of-chapter Exercise (15 questions, not 20). Unchanged by rationalisation.. Questions are referenced from the NCERT textbook for identification.