What do we call the contamination of air by harmful substances like gases and smoke?
air pollution
: Name one U.S. law that sets limits on amounts of certain air pollutants.
Clean Air Act
What man-made chemicals react with sunlight and destroy ozone molecules in the upper atmosphere?
Chlorofluorocarbons (CFCs).
Name two personal actions students can take to reduce energy use and help protect the atmosphere.
Turn off lights when leaving a room; walk or use public transportation; raise/lower thermostat settings to use less heating/cooling; choose energy-efficient appliances
What health problems can inhaling particulate matter cause?
Coughing, difficulty breathing, and other respiratory problems.
How can acid precipitation harm ecosystems?
It lowers the pH of lakes, ponds, and soil, which can kill fish, plants, and trees that cannot survive in more acidic conditions.
What is the brownish haze over many cities formed when nitrogen and carbon compounds react in sunlight?
photochemical smog
Give two examples of renewable energy sources mentioned that help reduce air pollution.
Solar power and wind power (also geothermal energy).
What forms when gases containing nitrogen and sulfur react with water and oxygen in the atmosphere?
Acid precipitation (acid rain or snow).
What layer of the atmosphere helps block ultraviolet (UV) rays?
ozone layer
Besides human health, name one other thing that particulate matter or smog can damage.
Plant life (reduces photosynthesis), buildings (soot and corrosion), or visibility (haze)
What term describes tiny solid or liquid particles in the air such as smoke, dust, and dirt?
particulate matter
What international agreement aims to reduce the use of CFCs?
Montreal Protocol
What common human activity releases nitrogen and carbon compounds that lead to smog?
Burning fossil fuels (for vehicles and power plants).
Explain why ozone near Earth's surface is considered harmful while ozone high in the atmosphere is helpful.
Ozone near Earth's surface is a major component of smog and can harm breathing and plant life; ozone high in the atmosphere absorbs harmful UV rays and protects living organisms.
Explain one reason given for why more people don’t adopt technologies like solar panels and wind turbines.
Expense (cost) and suitability of the technology to a particular area.
Name two natural processes that can release particulate matter into the air.
Volcanic eruptions and forest fires.
Describe one way photochemical smog formation is connected to daily human behavior.
It forms when emissions from cars and power plants (burning fossil fuels) release nitrogen and carbon compounds that react in sunlight—so driving and energy use contribute directly
What is the approximate pH of normal rainwater?
5.6
How does a thinner ozone layer affect human health?
It allows more UV rays to reach Earth’s surface, increasing risks like skin cancer.