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Cbse science quize


1. Which of the following is the lightest metal ?
(A) Mercury
(B) Silver
(C) Lithium
(D) Lead

2. The most important ore of Aluminium is —
(A) Bauxite
(B) Calamine
(C) Calcite
(D) Galena

3. The element present in the largest amount in rocks and minerals is —
(A) Carbon
(B) Silicon
(C) Hydrogen
(D) Aluminium

4. An alloy used in making heating elements for electric heating devices is —
(A) Solder
(B) Alloysteel
(C) Nichrome
(D) German Silver

5. German Silver is an alloy of —
(A) Copper, Silver & Nickel
(B) Silver, Copper & Aluminium
(C) Zinc, Copper & Nickel
(D) Silver, Zinc & Nickel

6. Air is a/an —
(A) Compound
(B) Element
(C) Mixture
(D) Electrolyte

7. Which of the following is the best conductor of Electricity ?
(A) Ordinary water
(B) Sea water
(C) Boiled water
(D) Distilled water

8. Balloons are filled with —
(A) Helium
(B) Oxygen
(C) Nitrogen
(D) Argon

9. The charcoal used to decolourise raw sugar is —
(A) Animal charcoal
(B) Sugar charcoal
(C) Cocoanut charcoal
(D) Wood charcoal

10. The most abundant metal in the earth’s crust is —
(A) Zinc
(B) Copper
(C) Aluminium
(D) Iron

11. The gas used to extinguish fire is —
(A) Neon
(B) Nitrogen
(C) Carbon dioxide
(D) Carbon Monoxide

12. In which of the following activities Silicon Carbide is used ?
(A) Making cement and glass
(B) Disinfecting water and ponds
(C) Making castes for statues
(D) Cutting very hard substances

13. The element common to all acids is —
(A) Oxygen
(B) Hydrogen
(C) Nitrogen
(D) Sulphur

14. Gobar gas contains mainly —
(A) Methane
(B) Carbon dioxide
(C) Butane
(D) Carbon Monoxide

15. The most malleable metal is —
(A) Silver
(B) Gold
(C) Aluminium
(D) Sodium

16. Tetraethyl lead is used as —
(A) Mosquito repellent
(B) Pain Killer
(C) Fire extinguisher
(D) Petrol additive

17. Which of the following is used in beauty parlours for hair setting ?
(A) Phosphorus
(B) Sulphur
(C) Chlorine
(D) Silicon

18. Which of the following is a non-metal that remains liquid in room temperature ?
(A) Bromine
(B) Chlorine
(C) Helium
(D) Phosphorus

19. From which mineral is radium obtained —
(A) Limestone
(B) Haematitie
(C) Pitchblende
(D) Rutile

20. What is laughing gas ?
(A) Carbon dioxide
(B) Sulphur dioxide
(C) Nitrogen Dioxide
(D) Nitrous oxide

21. Which of the following is used as a material for making protective windows in space probes ?
(A) Steel
(B) Graphite
(C) Tungsten
(D) Diamond

22. Which form of phosphorus is used in safety metals?
(A) Red Phosphorus
(B) White Phosphorus
(C) Yellow Phosphorus
(D) Black Phosphorous

23. Stainless steel is an alloy of —
(A) Iron, Carbon and Nickel
(B) Iron and Manganese
(C) Iron, Chromium and Zinc
(D) Iron, Chromium and Nickel

24. Which of the following is not correctly matched ?
(A) Galena : Lead Sulphide
(B) Green vitriol : Copper sulphate
(C) Plaster of Paris : Calcium sulphate
(D) Calomel : Mercurous Chloride

25. Which of the following metals forms an amalgum with other metals ?
(A) Lead
(B) Tin
(C) Zinc
(D) Mercury

Answers: 
1. (C) 2. (A) 3. (B) 4. (C) 5. (C) 6. (C) 7. (B) 8. (A) 9. (D) 10. (C) 11. (C) 12. (D)
13. (B) 14. (A) 15. (B) 16. (D) 17. (B) 18. (A) 19. (C) 20. (D) 21. (D) 22. (A) 23. (D) 24. (B) 25. (D)

Comments

  1. Phosphorous is not a metal the question number 22 should be safety matches

    ReplyDelete
  2. You made numerous nice ideas there. I done a search on the issue and learnt nearly all peoples will agree with your blog.
    Cbse exam

    ReplyDelete

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