Sets
Chemistry Set 18
30 questions 1. When an iron nail is dipped in copper sulphate solution, the blue colour of the solution fades because:
2. The white powder formed on burning a magnesium ribbon in air is:
3. Consider the following statements:
(I) Excessively acidic soil can be treated with lime.
(II) Basic soil can be treated with organic matter such as manure and composted leaves.
(III) Excessive use of chemical fertilisers can make soil acidic.
Which of the above is/are correct?
4. Handpicking is a convenient method when the particles to be removed are:
5. The percentage of carbon present in the earth's crust in the form of minerals is:
6. The pH scale generally measures pH from:
7. Which of the following metals is found in nature in the free state?
8. The first woman to receive the Shanti Swarup Bhatnagar Award in the field of chemical science was:
9. The brown substance formed during rusting of iron is chemically:
10. The first fullerene to be identified was:
11. N₂O₄ is correctly named as:
12. Basic substances are generally ______ to touch.
13. Friedrich Wöhler disproved the 'vital force' theory in 1828 by preparing:
14. Reducing the supply of oxygen to fat-containing food helps to:
15. Which of the following dissolves in kerosene and petrol but not in water?
16. A solid has a mass of 300 g and a volume of 120 cm³. Its density is:
17. Lichens are formed by the association of:
18. On heating in air, cinnabar is first converted into:
19. Sodium chloride contains sodium and chlorine in the mass ratio of 23:35.5. The mass of chlorine required to react completely with 69 g of sodium is:
20. Nitrogen constitutes about what percentage of air?