Most Important Science GK Question ans Answer for SCC Exam

1. Carbon dioxide is called a greenhouse gas because

(A) Its concentration remains always higher than other gases
(B) It is used in photosynthesis
(C) It absorbs infrared radiation
(D) It emits visible radiation

Answer: It absorbs infrared radiation

2. What is the major role of a greenhouse gas that contributes to temperature rise of the earth’s surface?

(A)Transparent to both incoming sunlight and outgoing infrared radiation
(B) Stops both incoming sunlight and outgoing infrared radiation
(C) Lets outgoing infrared radiation pass through but stops incoming sunlight
(D) Lets incoming sunlight pass through but stops outgoing infrared radiation

Answer: Stops both incoming sunlight and outgoing infrared radiation

3. Which among the following nontoxic gases helps in formation of enzymes which ripen fruit?

(A) Acetylene
(B) Ethane
(C) Methane
(D) Carbon dioxide

Answer:Ethane

4.Which one among the following is strong smelling agent added to LPG cylinder to help in the detection of gas leakage?

(A) Ethanol
(B) Thioethanolamine
(C) Methane
(D) Chloroform

Answer:Thioethanolamine

5.The major component in LPG is

(A) Methane
(B) butane
(C) ethane
(D) propane

Answer:butane

6.The vertical movement of air is termed as

(A) wind
(B) Air Current
(C) Air turbulence
(D) Air mobility

Answer: Air Current

7.Which of the following is not a method of preparing oxygen?

(A) Electrolysis of water
(B) Fractional distillation of liquid air
(C) Decomposition of potassium permanganate
(D) Decomposition of manganese dioxide

Answer:Fractional distillation of liquid air

8.Oxygen and ozone are

(A) allotropes
(B) isomers
(C) isotopes
(D) isobars

Answer:allotropes

9. Ozone layer is present in

(A) Troposphere
(B) Ionosphere
(C) Stratosphere
(D) Exosphere

Answer:Ionosphere

10. Which is the lowest layer of the atmosphere?

(A) Troposphere
(B) Stratosphere
(C) Mesosphere
(D) Thermosphere

Answer:Troposphere

11. Which one of the following is a major constituent of Biogas?

(A) Carbon dioxide
(B) Methane
(C) Hydrogen
(D) Nitrogen Dioxide

Answer:Methane

12.Sea breeze is formed during

(A) Day time
(B) Night time
(C) Both
(D) Seasonal

Answer:Day time

13.The Refrigerant 'FREON' is

(A) Calcium Tetra Flouride
(B) Diflouro Dichloro Methane
(C) Flourspar and Felspar
(D) Hydrofluosilicic Acid

Answer:Diflouro Dichloro Methane

14.Now a days, Yellow lamps are frequently used as street lights. Which among the following gases, is used in these lamps?

(A) Sodium
(B) Neon
(C) Hydrogen
(D) Nitrogen

Answer:Sodium

15.The atmospheric air is held to the earth by

(A) Gravity
(B) Winds
(C) Clouds
(D) Rotation of the earth

Answer:Gravity

16.The Noble Gas used for the treatment of cancer is ___?

(A) Helium
(B) Argon
(C) Krypton
(D) Radon

Answer:Argon

17. The optimum dissolved oxygen level (in mg/litre) required for survival of aquatic organisms is

(A) 4 – 6
(B) 2 – 4
(C) 8 – 10
(D) 12 - 16

Answer:4 – 6

18.Troposphere is the hottest part of the atmosphere because

(A) it is closest to the Sun
(B) there are charged particles in it
(C) it is heated by the Earth’s surface
(D) heat is generated in it

Answer:it is heated by the Earth’s surface

19.Which of the following is the lightest gas?

(A) hydrogen
(B) helium
(C) xenon
(D) radon

Answer: hydrogen

20.What is the chemical name of Laughing Gas?

(A) Silver nitrate
(B) Sodium carbonate
(C) Calcium sulphat
(D) Nitrous oxide

Answer:Nitrous oxide