What is acid rain and what is its pH compared to normal rain?
Rain that is more acidic than normal due to pollution (1) and its pH is 4.2-4.4 (can go to 2) (1)
Normal rain is 5.6 (1)
(3)
What is global warming?
The increase in Earth’s average temperature due to greenhouse gases (1)
What is combustion?
Burning for energy, heat etc. (1)
What are greenhouse gases?
Gases that trap heat in Earth’s atmosphere (1)
What number do you call for emergency fire services?
999 (Qatar) (but if given another country e.g. birthplace, accept) (1)
Which two gases mainly cause acid rain?
Sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) (2)
Name one major cause of global warming
(One from:) Burning fossil fuels, deforestation, excessive emissions, industrialisation (1)
What are the three things needed for combustion?
Oxygen, heat, fuel (fire triangle) (3)
Name two greenhouse gases
(Any two from:) Carbon dioxide (CO₂), methane (CH₄), water vapour (H2O), nitrous oxide (2)
What is the best way to put out a small grease fire in the kitchen?
Smother it with a lid or use a fire extinguisher (NEVER use water) (2)
How does acid rain affect aquatic life?
It lowers the pH of water, making it too acidic for fish and other organisms to survive (3)
What is the effect of global warming on ice caps?
It causes them to melt, leading to rising sea levels (1)
What are the two types of combustion?
Complete and incomplete (2)
How does methane compare to carbon dioxide in terms of warming potential?
Methane is about 25 times more effective at trapping heat than CO₂ over a 100-year period (2)
What does a fire extinguisher do?
To remove one or more elements of the fire triangle (heat, fuel, oxygen) and stop the fire (3)
What chemical reaction happens when sulfur dioxide mixes with water in the atmosphere?
SO₂ + H₂O → H₂SO₃ (sulfurous acid), which can further oxidize to form H₂SO₄ (sulfuric acid) (2)
How does deforestation contribute to global warming?
Trees absorb CO₂, so cutting them down increases the amount of CO₂ in the atmosphere (2)
What is the main difference between complete and incomplete combustion?
Complete combustion produces carbon dioxide (1) and water (2), while incomplete combustion produces carbon monoxide (3) and soot (4) due to a lack of oxygen.
What is the main source of methane emissions?
Livestock farming (cow digestion and manure) and landfill decomposition (3)
Why should you test smoke alarms regularly?
To ensure they are working and can alert you in case of fire (1)
How do limestone and marble structures get damaged by acid rain?
Acid rain reacts with calcium carbonate (1) in the stone, producing calcium sulfate, carbon dioxide, and water, which weakens the structure (2)
What is the albedo effect, and how does it relate to global warming?
How much sunlight is reflected by Earth’s surface.
Darker surfaces make warming worse. (4)
Why is carbon monoxide dangerous, and how is it produced in combustion?
Carbon monoxide is toxic because it binds to haemoglobin (1) in the blood, reducing oxygen transport. It is produced during incomplete combustion when there isn’t enough oxygen to form CO₂ (2)
How does the greenhouse effect differ from global warming?
The greenhouse effect is a natural process that warms Earth by trapping heat (2), while global warming is the enhanced effect caused by human activities increasing greenhouse gas levels (2)
What are the five classes of fire extinguishers, and what are they used for?
Class A: Ordinary combustibles (wood, paper).
Class B: Flammable liquids (gasoline, oil).
Class C: Electrical fires.
Class D: Metal fires.
Class K: Cooking oil and grease fires. (5)