Causes of Atmospheric Pollution Flashcards

All 12 cards in this deck

Which elements are found in most fuels, including coal?

Carbon and/or hydrogen, and some fuels also contain sulfur as an impurity.

Which gases and solids may be released into the atmosphere when a fuel is burned?

Carbon dioxide, water vapour, carbon monoxide, sulfur dioxide and oxides of nitrogen, plus solid particles (soot) and unburned hydrocarbons that form particulates.

How are carbon monoxide and soot (carbon particles) produced when a fuel burns?

By incomplete combustion, because there is insufficient oxygen.

How is sulfur dioxide produced when a fuel such as coal or petrol is burned?

The sulfur impurities in the fuel react with (burn in) oxygen to form sulfur dioxide, $SO_2$.

Why are oxides of nitrogen formed in car engines?

Car engines work at high temperatures, so nitrogen from the air reacts with oxygen from the air.

What are the steps to predict the products of burning a fuel and write the balanced equation?

e.g. methane, $CH_4$, burned in plenty of air

1. Carbon in the fuel gives carbon dioxide, hydrogen gives water vapour (sulfur would give sulfur dioxide): $CH_4 + O_2 \rightarrow CO_2 + H_2O$

2. Balance C, then H, then O: $CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O$

3. In a limited supply of air, give carbon monoxide and/or soot instead of carbon dioxide.

Why is carbon monoxide a dangerous pollutant that is hard to detect?

It is a toxic gas, and it is colourless and odourless so it is not easily detected.

What two problems are caused by sulfur dioxide and oxides of nitrogen in the air?

They cause respiratory problems in humans and they cause acid rain.

What problems are caused by particulates in the atmosphere?

Global dimming and health problems for humans.

True or false? Acid rain can erode limestone buildings and statues and damage plants and trees.

True. Sulfur dioxide and oxides of nitrogen dissolve in water in the air to make rain acidic, which reacts with limestone and harms plants and lakes.

True or false? Particulates in the atmosphere cause global dimming because they trap heat near the Earth's surface.

False. They reflect sunlight back into space, so less sunlight reaches the surface — they also cause human health problems.

What is the environmental benefit of removing sulfur impurities from a fuel before it is burned?

Less sulfur dioxide is emitted, so there is less acid rain (and fewer respiratory problems).