Challenge No 2 - Fire

Why does a bike turn reddish-brown when left outside for months?

• Because of oxidation (fast)
• Because of rapid combustion
• Because of mold growth
• Because of slow oxidization (rust)

How do firefighters stop fires using oxidization?

• By increasing temperature
• By adding more oxygen
• By cutting off oxygen supply
• By applying fuel

What happens when you blow on a campfire?

• The fire turns blue because it mixes with water in the air
• The fire goes out because carbon and hydrogen disappear
• The fire gets smaller because the wind cools it down
• The fire gets brighter because more oxygen is added

What is oxidization?

• The moment fire begins
• A model showing fire’s requirements
• The visible part of a flame
• A slow chemical reaction with oxygen, producing heat or rust

What are the three things fire needs to burn?

• Heat, electricity, oxygen
• Oxygen, water, fuel
• Heat, fuel, oxygen
• Heat, water, fuel

Which of these is an example of ignition?

• A tree growing taller
• A rock rolling down a hill
• A match being struck
• A candle melting without a flame

Why do firefighters remove ignition sources?

• To prevent sparks and new flames
• To cool the fire
• To increase oxygen
• To starve the fire of fuel

What does combustion need to keep fire burning?

• Oxygen, water, heat
• Fuel, oxygen, heat
• Fuel, light, water
• Fuel, carbon, hydrogen

Which of these is an example of uncontrolled combustion?

• A wildfire spreading in a forest
• A rocket launching into space
• A car engine running smoothly
• A candle burning on a table

Why is controlled combustion useful?

• For cooking dinner and generating energy
• For creating explosions
• For safety demonstrations
• For producing smoke