CHAPTER-WISE 086 Science QUESTIONS | CBSE Class 10th | 2026

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📕 1. Chemical Reactions & Equations

1. Write a balanced chemical equation for:
   • Zinc + dilute HCl
   • Ferrous sulphate on heating
2. Define oxidation and reduction with one example each.
3. Identify the type of reaction:
   • CaO + H₂O → Ca(OH)₂
4. What is corrosion? Name two methods to prevent it.
5. Why should a chemical equation be balanced?

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📕 2. Acids, Bases and Salts

1. Define acids and bases in terms of H⁺ and OH⁻ ions.
2. What is the pH scale? State its importance in:
   • Tooth decay
   • Soil treatment
3. Write preparation and uses of:
   • Baking soda
   • Washing soda
   • Bleaching powder
4. Why is dilution of acid done by adding acid to water?
5. What happens when:
   • An acid reacts with a base?

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📕 3. Metals and Non-metals

1. Write two physical and two chemical properties of metals.
2. What is the reactivity series? Write one use.
3. Why are ionic compounds:
   • Hard
   • Conduct electricity in molten state?
4. What is corrosion? How is it prevented?
5. Difference between metals and non-metals.

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📕 4. Carbon and its Compounds

1. What are covalent bonds?
2. Define homologous series (two characteristics).
3. Difference between saturated and unsaturated hydrocarbons.
4. Write properties and uses of:
   • Ethanol
   • Ethanoic acid
5. Difference between soap and detergent.
6. Explain cleansing action of soap.