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1250 Important Chemistry MCQ Question and Answer PDF

4000 Important General Science MCQ Question & Answer in PDF Download

1.Carbon monoxide is an inflammable gas. Which one of the followings is also inflammable?

  • AHelium
  • BNitrogen
  • COxygen
  • DHydrogen
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Correct Answer : (D)

Hydrogen
Explanation:

2.Which one of the following metals does not react with water to produce Hydrogen?

  • APotassium
  • BCadmium
  • CSodium
  • DLithium
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Correct Answer : (B)

Cadmium
Explanation:

3.Ozone consists of

  • AOxygen only
  • BOxygen and Nitrogen
  • CHydrogen and Carbon
  • DOxygen and Carbon
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Correct Answer : (A)

Oxygen only
Explanation:

4.An atomic clock is based on transitions in

  • ASodium
  • BCaesium
  • CMagnesium
  • DAluminium
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Correct Answer : (B)

Caesium
Explanation:

5.The material used in the manufacture of lead pencil is

  • AGraphite
  • BLead
  • CCarbon
  • DMica
Answer / Hint Save Question Comment On Question
Correct Answer : (A)

Graphite
Explanation:

6.If all bullets could not be removed from gunshot injury of a man, it may cause poisoning by

  • AMercury
  • BLead
  • CIron
  • DArsenic
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

Lead
Explanation:

7.The noble gas used in radiotherapy is 

  • ANeon
  • BArgon
  • CRadon
  • DXenon
Answer / Hint Save Question Comment On Question
Correct Answer : (C)

Radon
Explanation:

8.Galena is a mineral of

  • AIron
  • BGold
  • CLead
  • DCalcium
Answer / Hint Save Question
Correct Answer : (C)

Lead
Explanation:

9.Magnesium is an alloy of

  • AAluminium and Magnesium
  • BMagnesium and Tin
  • CAluminium and Zinc
  • DManganese and Magnesium
Answer / Hint Save Question
Correct Answer : (A)

Aluminium and Magnesium
Explanation:

10.The metallurgical process in which a metal is obtained in a fused state is called

  • ASmelting
  • BRoasting
  • CCalcinations
  • Dfroth floatation
Answer / Hint Save Question
Correct Answer : (A)

Smelting
Explanation:

11.Two elements which are used to absorb neutrons to control the chain reaction during nuclear fission are

  • ABoron and cadmium
  • BBoron and plutonium
  • CCadmium and uranium
  • DUranium and boron
Answer / Hint Save Question
Correct Answer : (A)

Boron and cadmium
Explanation:

12.Supersonic jet causes pollution by thinning of

  • AO3 layer
  • BO2 layer
  • CSO2 layer
  • DCO2 layer
Answer / Hint Save Question Comment On Question
Correct Answer : (A)

O3 layer
Explanation:

13.Which of the following metals causes Itai-Itai disease?

  • ACadmium
  • BChromium
  • CCobalt
  • DCopper
Answer / Hint Save Question
Correct Answer : (A)

Cadmium
Explanation:

14.Which one of the following minerals is found in monazite sand?

  • APotassium
  • BUranium
  • CThorium
  • DSodium
Answer / Hint Save Question
Correct Answer : (C)

Thorium
Explanation:

15.Now-a-says yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?

  • ASodium
  • BNeon
  • CHydrogen
  • DNitrogen
Answer / Hint Save Question
Correct Answer : (A)

Sodium
Explanation:

16.Which of the following could be used as fuel in propellant or rockets?

  • ALiquid Hydrogen + Liquid Nitrogen
  • BLiquid Oxygen + Liquid Argon
  • CLiquid Nitrogen + Liquid Oxygen
  • DLiquid Hydrogen + Liquid Oxygen
Answer / Hint Save Question Comment On Question
Correct Answer : (D)

Liquid Hydrogen + Liquid Oxygen
Explanation:

17.Hard steel contains

  • A2 to 5 per cent carbon 
  • B0.5 to 1.5 per cent carbon
  • C0.1 to 0.4 per cent carbon
  • D0.01 to 0.04 per cent carbon
Answer / Hint Save Question
Correct Answer : (B)

0.5 to 1.5 per cent carbon
Explanation:

18.Cement is formed by strongly heating a mixture of

  • ALimestone and graphite
  • BLimestone and clay
  • CChalk and graphite
  • DClay and graphite
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

Limestone and clay
Explanation:

19.The main chemical constituent of clay is

  • Asilicon oxide
  • Baluminium borosilicate
  • Czeolites
  • Daluminium silicate
Answer / Hint Save Question Comment On Question
Correct Answer : (D)

aluminium silicate
Explanation:

20.The mineral containing both magnesium and calcium is

  • AMagnesite
  • BCalcite
  • CCarnallite
  • DDolomite
Answer / Hint Save Question Comment On Question
Correct Answer : (D)

Dolomite
Explanation:
4000 Important General Science MCQ Question & Answer in PDF Download

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