CBSE Class 9 Social Science Atmosphere and Climate (Class 9 NCERT New) Quiz 5

1. A large volume of air that has the same temperature and humidity throughout is called a(n)

A front B air mass C convection current D tropospheric anomoly

2. Convection moves as a current because cool air sinks and warm air rises. Air moves this way due to changes in

A air pressure B density C radiation level D amounts of conduction

3. The main chemicals responsible for breaking down ozone in the stratosphere are

A sulfuric and nitric acids B VOCs C carbon dioxide and carbon monoxide D CFCs

4. This brown haze forms when sunlight interacts with certain types of air pollutants.

A smog B temperature inversions C dust storms D tropospheric ozone

5. This is a dangerous pollutant in the troposphere, but protects life as a concentrated layer in the stratosphere

A oxygen B nitrogen C ozone D carbon dioxide

6. As a result of this treaty, manufacture of CFCs has fallen dramatically.

A Clean Air Act B Cartegena Convention C Clean Water Act D Montreal Protocol

7. Pollutants that are released directly to the troposphere, like soot and carbon monoxide, are:

A primary air pollutants B secondary air pollutants C point source air pollutants D nonpoint source air pollutants

8. Secondary air pollutants

A are less toxic than primary air pollutants B form when primary pollutants undergo chemical reactions C are more toxic than primary air pollutants D stay in the second layer of Earth's

9. The main source of the pollutants in photochemical smog is

A exhaust of vehicles B soot from factory smokestacks C water vapor released from power plants D combustion of waste

10. Fossil fuels are carbon-containing fuels that formed millions of years ago from

A the combustion of various types of igneous rocks B substances that reached Earth via meteoroids C the remains of once-living organisms D the cooling of Earth's surface during its formation