Chemistry Set 20 FAQs

1. Metals that produce a ringing sound on striking a hard surface are said to be:

2. When vinegar reacts with baking soda in an open flask, the final mass differs from the initial mass because:

3. Consider the following statements: (I) Ionic compounds conduct electricity in the solid state. (II) Ionic compounds conduct electricity in water because their ions are free to move. (III) Sugar dissolves in water but does not conduct electricity. Which of the above is/are correct?

4. Which of the following converts ethanol to ethanoic acid?

5. The factor essential for effective filtration is:

6. The relative density of a substance with respect to water has the unit:

7. In Kannauj, the natural perfume Mitti ka Ittar is made using the traditional method called:

8. In a hydrogen molecule, each hydrogen atom attains the electronic configuration of:

9. A decomposition reaction carried out by heating is called:

10. Consider the following pairs: (I) Oxidising agent – Acceptor of electrons (II) Reducing agent – Donor of electrons (III) Oxidation – Gain of electrons Which of the pairs given above is/are correctly matched?

11. Which of the following exists only as atoms because its atoms are stable?

12. The Periodic Law is essentially the consequence of the periodic variation in:

13. The molar mass of a substance is the mass of:

14. Detergents remain effective in hard water because their charged ends:

15. Which allotrope of carbon conducts electricity?

16. Carbon cannot reduce the oxides of sodium, magnesium, calcium and aluminium because these metals have more affinity for oxygen than for:

17. The paediatrician who developed and implemented the treatment for dehydration using Oral Rehydration Solution (ORS) was:

18. To obtain the molecular formula from the empirical formula, the additional data required is the:

19. The acidic properties of acids are due to the formation of which ions in solution?

20. In paper chromatography, at the start of the experiment, the solvent level should be:

21. Compounds with identical molecular formula but different structures are called:

22. Fermentation of molasses obtained from sugarcane juice gives:

23. In the reaction 2Na + H₂ → 2NaH, sodium is oxidised because:

24. Mendeleev left several gaps in his table because he proposed that some elements were still:

25. Dalton's atomic theory could not explain the:

26. Medicines used for treating indigestion are called:

27. The 'p' in pH stands for 'potenz', a German word meaning:

28. A solution that cannot dissolve any more solute at a given temperature is called:

29. Following the prefix naming system, NH₃ is named:

30. Consider the following pairs: (I) Ethanol with conc. H₂SO₄ at 443 K – Ethene (II) Ethanol with sodium – Sodium ethoxide and hydrogen (III) Methane with chlorine in sunlight – Addition reaction Which of the pairs given above is/are correctly matched?