CHEMISTRY - AIR AND ATMOSPHERE - MULTIPLE CHOICE QUESTIONS - EX 5.1 (Part 1)

Fun, multiple-choice Quiz - of first part 15 questions from the Fill in the Blanks, Correcting Statements, and Matching sections into a  format.

Part 1: The Basics

1. Oxygen is necessary for respiration and which other process?

Photosynthesis Combustion Evaporation Nitrogen Fixation

2. What do we call the envelope of air that surrounds the Earth?

Exosphere Atmosphere Hydrosphere Biosphere

3. Which constituent of air is known as the "life supporting" gas?

Nitrogen Carbon Dioxide Oxygen Argon

4. When products of combustion hit anhydrous copper sulphate, what color does it turn? 

Yellow Blue Pink Colorless

5. What happens when clear limewater is exposed to air for a long time? 

It turns milky It turns pink It turns transparent It turns green

Part 2: Fact or Fiction?

6. Which of these are the REAL products of fuel combustion? 

Nitrogen and Water Vapour Carbon Dioxide and Water Vapour Oxygen and Nitrogen Carbon Dioxide and Ash only

7. How is coal primarily classified as a fuel?

Industrial fuel Household fuel Non-combustible material Aviation fuel

8. What is the true purpose of LPG in our homes?

To extinguish fires As a combustible household fuel To purify the air To manufacture fertilizers

9. What does water do to anhydrous copper sulphate?

Makes it colorless Turns blue into white Turns white into blue Turns blue into pink

10. Is Oxygen necessary for the respiration of plants?

Yes, it is necessary No, plants only use CO2 No, plants do not respire Only during the day

Part 3: Master Matcher

11. Find the match: Products of combustion of a fuel?

Water and Carbon Dioxide Nitrogen gas Solid Carbon Pure Oxygen

12. Find the match: Percentage of Oxygen in air?

78% 0.03% 21% 1%

13. Find the match: Percentage of Nitrogen in air?

78% 21% 0.94% 100%

14. Find the match: A gas which turns limewater milky?

Argon Carbon Dioxide Helium Oxygen

15. Find the match: A petroleum product used as household fuel?

Coal Wood Kerosene oil Petrol

🔬 Scientist's Lab Notes

🧪 

Key Concepts Review

Before you finish, remember these vital chemical signs:

Carbon Dioxide Test: Limewater changes from clear to milky when CO2 is present.

Water Vapour Test: Anhydrous copper sulphate changes from white to blue when it touches water.

Air Composition: The air is a mixture consisting of 78.3% Nitrogen, 21% Oxygen, and 1% other gases including Noble Gases (Argon, Helium, etc.) and Carbon Dioxide.

Combustion Equation: 

{Fuel} + {Oxygen} --> {Carbon dioxide} + {Water vapour} + {Heat}.