Class 10 Science Chapter 2: Acids, Bases and Salts

Chapter 2 of the NCERT Class 10 Science textbook “Science”.

Chapter at a glance

This part introduces what acids and bases are in everyday terms, their common properties, how we test them using indicators, and the basic neutralisation reaction that forms salts and water. You will learn simple tests (taste/household examples are only described; never taste chemicals), colour changes of common indicators, and why acid–base neutralisation matters. The focus is on conceptual understanding and typical classroom observations.

What you will learn: You will learn the observable properties of acids and bases, how indicators show those properties, and the neutralisation reaction that links acids, bases and salts.

Why it matters: These ideas explain many everyday things: why lemon tastes sour, why antacid tablets relieve acidity, and how cleaning agents or fertilisers behave. They are the foundation for pH and for making salts in later parts.

Key concepts

Acids — Acids are substances that taste sour and turn blue litmus red.
Bases (Alkalis) — Bases feel soapy or bitter and turn red litmus blue.
Indicators — Indicators are substances that change colour when put in acids or bases.
Neutralisation — Neutralisation is the reaction where an acid and a base form a salt and water.

What the chapter covers

Try at Home — A safe, teacher-supervised observation you can try at home using household items.
Why Questions — Short explanations that clarify common 'why' doubts.

Remember for the exam

Always state the indicator used and the observed colour change.
Neutralisation usually gives salt + water, not gas.

Common mistakes

Mistake: Using the word 'litmus gives blue in acid' without checking which litmus was used. Better: State the specific litmus paper (blue or red) and the observed change.
Mistake: Saying neutralisation always produces gas. Better: Write 'salt and water' as usual products, and mention gas only when carbonate or metal reacts.
Mistake: Calling baking soda an 'acid' because it reacts with vinegar. Better: Identify baking soda (sodium bicarbonate) as a compound that behaves basic in water.

These notes are a study aid. Check important facts against your textbook.

Study this chapter

A clear study guide that explains the chapter step by step
Quick revision for the day before a test
Practice quizzes that show which ideas need more work
An AI tutor to ask questions about “Acids, Bases and Salts”

Start learning free

Try it in the virtual lab

Crystallisation of copper sulphate or alum