4.5.2 Burning and Rusting Flashcards
What is needed for burning?
Air/ Oxygen is needed for burning.
When the ______ in air is ______ ______, burning stops.
Oxygen, used up
Refer to picture 1, write down which f ______ go out the last. Why?
flames
C
The larger the beaker, the more the air in it. And it takes longer time for the fire to use up the oxygen, so the longer the time for the flame to go out.
The greater the s ______ of ______ to a burning object, the ______ it burns.
supply, oxygen, longer
Why do people fan the burning charcoal when lighting a barbecue?
Provides more air, ie oxygen.
How can we put out the flames on a hotpot stove?
Turn off the stove which stop supplying air (which consists of oxygen)
How do the following equipments work to put out the fire?
Sand bucket
Sand bucket
Put the sand on the fire to cover them up and cut off the oxygen supply
How do the following equipments work to put out the fire?
Fire blanket
Put the blanket on the fire and cover them up to cut off the oxygen supply
How do the following equipments work to put out the fire?
Fire Extinguisher
Fire Extinguisher
Carbon dioxide will sink under oxygen and separate the oxygen and the fuel. No oxygen supply’s to the fuel, so the fire stops.
Some types of gases are produced during burning. Name one
Carbon dioxide
Putting lime water in a glass full of gases produced by burning candle, and the lime water will ______ ______.
This shows that the carbon dioxide (is/ is not ) produced during burning.
is
Turn milky
is
When people escape from a fire, they cover their n______ and m ______ with ______ ______ which can f______ o______ some of the h______ substances in the smoke and i______ people’s chance of survival.
noses, mouths, wet towels, filter out, harmful, increase
Iron rusts easily when it is in contact with ______ and ______.
air, water
What are the methods help to prevent rusting?
- wrapping iron hangers in plastic
- painting iron fences
- putting anti-rust oil on a bicycle chain
