Reducing Acid Rain Or Its Effects

The video explains acid rain as a dilute solution of nitric and sulfuric acids, with a pH around 4. It discusses the sources of nitrogen and sulfur in acid rain, primarily from motor vehicles and power stations. Initial solutions like using tall chimneys and adding limestone to lakes were partly successful. A better method is scrubbing, using alkalis like lime or seawater to trap sulfur dioxide before it reaches the atmosphere. In refineries, sulfur is removed from crude oil through hydrodesulfurisation. To reduce nitric acid, catalytic converters in vehicles convert nitrogen oxides back to nitrogen and oxygen. The best prevention is stopping sulfur and nitrogen oxides from entering the atmosphere.

What is the primary source of nitrogen in nitric acid found in acid rain?

• Burning of coal in power stations

• Evaporation from oceans

• Combination of atmospheric nitrogen and oxygen in vehicle engines

• Volcanic eruptions

What was the initial method used to neutralize acid rain in Swedish lakes?

• Introducing fish that can tolerate acidic water

• Using tall chimneys to disperse pollutants

• Adding lime to the lakes

• Planting trees around the lakes

What is the chemical reaction that occurs when calcium oxide is used in the scrubbing process?

• Calcium oxide reacts with carbon dioxide to form calcium carbonate

• Calcium oxide reacts with water to form calcium hydroxide

• Calcium oxide reacts with nitrogen dioxide to form calcium nitrate

• Calcium oxide reacts with sulfur dioxide to form calcium sulfate

What is the main drawback of using scrubbers in power stations?

• They reduce the efficiency of power stations

• They are too expensive to install

• They produce harmful by-products

• They increase the emission of carbon dioxide

How do catalytic converters help in reducing acid rain?

• By converting sulfur dioxide into sulfur trioxide

• By increasing fuel efficiency

• By converting nitrogen oxides back into nitrogen and oxygen

• By trapping carbon monoxide