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1250 Important Chemistry MCQ Question and Answer PDF

4000 Important General Science MCQ Question & Answer in PDF Download

1.The purity of gold is expressed in carats. The purest form of gold is

  • A24 carats
  • B99.6 carats
  • C91.6 carats
  • D22 carats
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Correct Answer : (A)

24 carats
Explanation:

2.The lustre of the metal is because of

  • AThe lustre of the metal is because of
  • BHigh polish
  • CReflection of light due to the presence of free electrons
  • DAbsorption of light due to the presence of cavities
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Correct Answer : (C)

Reflection of light due to the presence of free electrons
Explanation:

3.One of the following is used to dissolve noble metals. That is

  • ANitric acid
  • BHydrochloric acid
  • CSulphuric acid
  • DAqua ragia
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Correct Answer : (D)

Aqua ragia
Explanation:

4.The most malleable metal is

  • APlatinum
  • BSilver
  • CIron
  • DGold
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Correct Answer : (D)

Gold
Explanation:

5.Percentage of carbon in steel ranges from

  • A0.1 to 1.5
  • B1.5 to 3.0
  • C3.0 to 4.0
  • D4.0 to 6.0
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Correct Answer : (A)

0.1 to 1.5
Explanation:

6.The most abundant inert gas in the atmosphere is

  • AHelium
  • BNeon
  • CArgon
  • DKrypton
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Correct Answer : (C)

Argon
Explanation:

7.Which metal is extracted from sea water?

  • APotassium
  • BMagnesium
  • CAluminium
  • DBeryllium
Answer / Hint Save Question
Correct Answer : (B)

Magnesium
Explanation:

8.Percentage of lead in lead pencils is

  • A0
  • B31 to 66
  • C40
  • D80
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Correct Answer : (A)

0
Explanation:

9.The gas which turns into liquid at the lowest temperature among the following is

  • AHydrogen
  • BOxygen
  • CHelium
  • DNitrogen
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Correct Answer : (A)

Hydrogen
Explanation:

10.Gunpowder consists of a mixture of

  • ASand and TNT
  • BTNT and charcoal
  • CNitre, sulphur and charcoal
  • DSulphur, sand and charcoal
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Correct Answer : (C)

Nitre, sulphur and charcoal
Explanation:

11.Which gas does not form the part of atmosphere?

  • ANitrogen
  • BHelium
  • CChlorine
  • DNone of the above
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Correct Answer : (C)

Chlorine
Explanation:

12.White coal is

  • AUranium
  • BHydro-electricity
  • CDiamond
  • DHydro-electricity
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Correct Answer : (D)

Hydro-electricity
Explanation:

13.The maximum Water Vapour content in the atmosphere is 

  • A2 to 3 per cent
  • B3 to 4 per cent
  • C4 to 5 per cent
  • D5 to 6 per cent
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

3 to 4 per cent
Explanation:

14.What are the number of moles of CO2 which contains 16 g of oxygen?

  • A0.5 mole
  • B0.2 mole
  • C0.4 mole
  • D0.25 mole
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Correct Answer : (A)

0.5 mole
Explanation:

15.The amount of chlorine available in water after disinfection is called as 

  • AFree chlorine
  • BResidual chlorine
  • CFree available chlorine
  • DCombined available chlorine
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Correct Answer : (B)

Residual chlorine
Explanation:

16.Photo oxidation process is initiated by

  • ALight
  • BHeat
  • COxygen
  • DCatalyst
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Correct Answer : (A)

Light
Explanation:

17.Ultraviolet radiation striking the earth is due to the depletion of

  • ACarbon monoxide
  • BCarbon dioxide
  • COzone
  • DOxygen
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Correct Answer : (C)

Ozone
Explanation:

18.Major gaseous pollutant of the thermal power station is

  • AH2S
  • BNH3
  • CNO2
  • DSO2
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Correct Answer : (D)

SO2
Explanation:

19.The tip of the match-stick contains

  • APhosphorus pentoxide
  • BWhite phosphorus
  • CRed phosphorus
  • DPhosphorus trichloride
Answer / Hint Save Question
Correct Answer : (C)

Red phosphorus
Explanation:

20.Which of the following substance is highly plastic?

  • AQuartz
  • BMica
  • CGranite
  • DClay
Answer / Hint Save Question Comment On Question
Correct Answer : (D)

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

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