10 MOST REPEATED MCQs (2015–2025) for 086 Science | Class 10th CBSE | 2026

1. The reaction in which heat is released is called
   👉 Exothermic reaction
2. Rusting of iron is an example of
   👉 Oxidation
3. pH value of acidic solution is
   👉 Less than 7
4. Which salt is used for softening hard water?
   👉 Washing soda
5. The metal stored in kerosene oil is
   👉 Sodium
6. Ionic compounds conduct electricity in
   👉 Molten state
7. Ethanol reacts with sodium to form
   👉 Hydrogen gas
8. Soap does not work well in hard water because
   👉 Scum is formed
9. Which gas is released when acid reacts with metal?
   👉 Hydrogen
10. Which bond is present in carbon compounds?
    👉 Covalent bond

These MCQs (or variations) appear almost every year.