topic 9

• What do fossil fuels contain that contributes to air pollution?

  Impurities like sulfur and nitrogen compounds
• What happens to sulfur compounds during combustion?

  They are oxidised to form sulfur dioxide
• What gases are formed from nitrogen compounds during combustion?

  Oxides of nitrogen, N Ox
• How much sulfur dioxide is produced from burning coal?

  A tiny amount of sulfur produces tons of SO₂
• What occurs during incomplete combustion of fossil fuels?

  Carbon is not fully oxidised, producing CO
• What are the environmental effects of particulates in the air?

  They cause lung damage and global dimming
• Why is carbon monoxide considered dangerous?

  It is toxic and binds to haemoglobin
• What is the main source of sulfur dioxide emissions?

  Combustion of fossil fuels containing sulfur
• How are nitrogen oxides formed during combustion?

  From a reaction between nitrogen and oxygen
• What happens when sulfur dioxide and nitrogen oxides mix with clouds?

  They form dilute sulfuric or nitric acid
• What are the consequences of acid rain?

  It kills trees and damages buildings
• What respiratory problems can sulfur dioxide and nitrogen oxides cause?

  They can cause respiratory issues when inhaled
• What are the main greenhouse gases and their effects?

  • Carbon dioxide: traps heat, essential for life
  • Methane: potent greenhouse gas from livestock
  • Water vapor: contributes to the greenhouse effect
• What is the greenhouse effect?

  It warms the Earth's surface by trapping heat
• How do human activities increase greenhouse gases?

  By burning fossil fuels and deforestation
• What is the link between increased carbon dioxide and climate change?

  Extra CO₂ from humans causes temperature rise
• What are potential consequences of climate change?

  Melting ice caps and rising sea levels
• How can rainfall patterns change due to climate change?

  Regions may receive too much or too little water
• What is a carbon footprint?

  Measure of greenhouse gases released over time
• Why are carbon footprints difficult to measure?

  Every stage of a product's life must be considered
• What factors can reduce a carbon footprint?

  Recycling, walking, and energy efficiency
• What is carbon capture and storage?

  Method to reduce emissions from fossil fuels
• What challenges exist in reducing carbon emissions?

  Economic growth concerns and technology development
• How can individuals help reduce greenhouse gas emissions?

  By choosing efficient products and lifestyles
• What gases did early volcanoes release?

  Carbon dioxide, nitrogen, and water vapour
• How did oceans absorb carbon dioxide?

  Water vapour condensed and dissolved CO₂
• What role did marine organisms play in carbon cycling?

  They extracted CO₂ to build shells and skeletons
• What is the chemical equation for photosynthesis?

  6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
• What was the atmosphere's composition about 200 million years ago?

  80% nitrogen, 20% oxygen, small gases
• How can scientists study changes in the atmosphere over time?

  By examining air bubbles in Antarctic ice cores
• What is the significance of sedimentary rocks in the atmosphere's evolution?

  They trap carbon dioxide and form fossil fuels
• What gases were present in the early atmosphere?

  Mostly carbon dioxide, little to no oxygen
• How did algae contribute to the atmosphere's evolution?

  They produced oxygen through photosynthesis
• What is the role of green plants in the atmosphere's evolution?

  They also photosynthesise and produce oxygen
• What is the significance of Antarctic ice cores in studying the atmosphere?

  They provide historical data on atmospheric changes
• What is the approximate age of the Earth?

  4.6 billion years
• What is the process of sediment formation from marine organisms?

  They build shells, which become sedimentary rocks
• How did the Earth's atmosphere change over billions of years?

  It evolved from CO₂-rich to oxygen-rich
• What is the relationship between fossil fuels and carbon dioxide?

  Fossil fuels release CO₂ when burned
• What is the impact of human activity on the greenhouse effect?

  It increases greenhouse gas concentrations