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1250 Important Chemistry MCQ Question and Answer PDF

4000 Important General Science MCQ Question & Answer in PDF Download

1.Glass is a

  • ASuperheated solid
  • BSupercooled liquid
  • CSupercooled gas
  • DSuperheated liquid
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Correct Answer : (B)

Supercooled liquid
Explanation:

2.A Balloon filled with helium rises in air because

  • AAir exerts an upward force on the balloon
  • BThe ballon is weightless
  • CHelium is less dense than air
  • DHelium pushes down on the air below the balloon
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Correct Answer : (C)

Helium is less dense than air
Explanation:

3.Which of the toxic heavy metals is found in modern tannery industries?

  • ANickel
  • BZinc
  • CChromium
  • DLead
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Correct Answer : (C)

Chromium
Explanation:

4.Which of the following contains high content of lead?

  • ACoal
  • BCooking gas
  • CHigh octane fuel
  • DLow octane fuel
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Correct Answer : (C)

High octane fuel
Explanation:

5.Stainless steel is an alloy of 

  • AChromium and carbon
  • BChromium, carbon and iron
  • CChromium and iron
  • DCarbon and iron
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

Chromium, carbon and iron
Explanation:

6.Which of the following is used in welding broken pieces of iron rails and machine parts?

  • AAluminium sulphate
  • BSolder
  • CAluminium power
  • DNone of the above
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Correct Answer : (C)

Aluminium power
Explanation:

7.The metals commonly used for electroplating are

  • AGold, Sodium and Chromium
  • BChromium, Copper and Nickel
  • CNickel, Lead and Chromium
  • DGold, Sodium and Potassium
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

Chromium, Copper and Nickel
Explanation:

8.Which of the following in automobile exhaust can cause cancer?

  • AOxides of nitrogen
  • BCarbon monoxide
  • CLead
  • DPolyclinic hydrocarbons
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Correct Answer : (D)

Polyclinic hydrocarbons
Explanation:

9.Electric bulbs are filled with :

  • ANitrogen
  • BCarbon dioxide
  • CArgon
  • DOxygen
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Correct Answer : (C)

Argon
Explanation:

10.The purest form of Iron is

  • ACast iron
  • BSteel
  • CPig iron
  • DWrought iron
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Correct Answer : (D)

Wrought iron
Explanation:

11.The gas used in the manufacture of vanaspati ghee from vegetable oil is

  • AOxygen
  • BCarbon dioxide
  • CHydrogen
  • DNitrogen
Answer / Hint Save Question Comment On Question
Correct Answer : (C)

Hydrogen
Explanation:

12.An example of semiconductor is

  • AGerman silver
  • BGermanium
  • CPhosphorous
  • DArsenic
Answer / Hint Save Question Comment On Question
Correct Answer : (B)

Germanium
Explanation:

13.Sea weeds are important source of

  • AIron
  • BChlorine
  • CBromine
  • DIodine
Answer / Hint Save Question
Correct Answer : (D)

Iodine
Explanation:

14.Slag is a name given for

  • AMolten iron
  • BMolten sand
  • CMolten alumina
  • DMolten calcium silicate
Answer / Hint Save Question Comment On Question
Correct Answer : (C)

Molten alumina
Explanation:

15.Which one of the following gases has the highest calorific value?

  • ANatural gas
  • BWater gas
  • CCoal gas
  • DIndene gas
Answer / Hint Save Question
Correct Answer : (D)

Indene gas
Explanation:

16.Which one of the following minerals is found in pure form?

  • AIron
  • BCopper
  • CBauxite
  • DManganese
Answer / Hint Save Question
Correct Answer : (B)

Copper
Explanation:

17.Among the fuels given below, the one with highest calorific value is

  • ACoke
  • BCoal
  • CWood
  • DNatural gas
Answer / Hint Save Question
Correct Answer : (D)

Natural gas
Explanation:

18.Coal is formed from

  • ACrude oil
  • BDeposit of animal waste
  • CCoke
  • DCompressed and hardened biomass
Answer / Hint Save Question
Correct Answer : (D)

Compressed and hardened biomass
Explanation:

19.Colour imparted to the Bunsen flame by strontium salt is

  • ABluish green
  • BApple green
  • CBrick red
  • DCrimson red
Answer / Hint Save Question
Correct Answer : (D)

Crimson red
Explanation:

20.The chemical name of  “laughing gas” is

  • ANitric oxide
  • BNitrogen dioxide
  • CNitrogen pentoxide
  • DNitrous oxide (N2O)
Answer / Hint Save Question
Correct Answer : (D)

Nitrous oxide (N2O)
Explanation:
4000 Important General Science MCQ Question & Answer in PDF Download

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