Topic 8E - Combustion Flashcards
revise for test
what is a fuel
a substance that contains stored energy
that can be released during burning
hydrogen + oxygen =
hydrogen + oxygen = water
metal + oxygen =
metal + oxygen = metal oxide
non-metal + oxygen =
non-metal + oxygen = non-metal oxide
what are the three factors on the fire triangle
Heat, Fuel, Oxygen
use the fire triangle theory to explain how to stop a fire and how does fire extinguisher work using this
they can be stopped by taking out one of its factors fire extinguishers work by cooling a fire or stop oxygen getting to the fuel
what is a independent variable
the variable in which you choose the values
what is a dependent variable
the variable you are measuring
Use words from the box to complete the sentences correctly. Not all the words will be used.
(burn, flames, hot, fire extinguisher, wet, wood)
(a) To light a bonfire, you need to make the wood very _____
(b) We can tell when the wood starts to burn, because we can see _____
(c) To put the fire out, we can use a _____
a) hot
b) flames
c) fire extinguisher
define combustion
a reaction in which burning happens
define hydrocarbon
a substance that contains only
hydrogen and carbon
define oxidation
a reaction in which a substance
combines with oxygen
Explain how water helps to put out a fire.
It cools the fire down/takes heat away from the
fire.
Explain what the fire triangle shows.
It shows the three factors needed for a fire to
burn.
Explain why you should not use water on burning oil.
It makes the fire explode and spread.
Name the product formed when magnesium metal burns in air and this reactions word equation
magnesium oxide
magnesium + oxygen = magnesium oxide
What happens to the mass of reactants and mass of products in this reaction? Tick one box.
A The mass of the products is more than the mass of the reactants.
B The mass of the products is less than the mass of the reactants.
C The mass of the products is the same as the mass of the reactants.
D The mass of the products is not comparable with the mass of the reactants.
C The mass of the products is the same as the mass of the reactants.
Name one non-metal oxide pollutant produced from the combustion of an impurity in fossil
fuels.
sulfur dioxide
Name one non-metal oxide pollutant produced by the high temperature inside a vehicle
engine when the engine is burning fossil fuels
nitrogen oxides
A tea light is a type of candle. The diagram shows apparatus used to investigate the effect of
the height of a candle on the time taken before the candle goes out.
Which is the independent variable in the experiment? Tick one box.
A height of candle
B the material of the container
C size of container
D time taken for candle to go out
A height of candle
A tea light is a type of candle. The diagram shows apparatus used to investigate the effect of
the height of a candle on the time taken before the candle goes out.
Which is the dependent variable in the experiment? Tick one box.
A height of candle
B the material of the container
C size of container
D time taken for candle to go out
D time for candle to go out
A tea light is a type of candle. The diagram shows apparatus used to investigate the effect of
the height of a candle on the time taken before the candle goes out.
Give a reason why the other variables need to be controlled.
Choose one of the control variables and suggest how it could be controlled.
To make the test fair/So that they don’t affect
the dependent variable
Use the same size of candle
The apparatus shown below is used to show what happens during the combustion of a
hydrocarbon fuel.
The thermometer will show that during the experiment the temperature:
A decreases
B increases
C stays the same
D varies
B increases
The blue cobalt chloride paper will change to pink because:
A water is being produced.
B oxygen is being produced.
C carbon dioxide is being produced.
D heat is being produced.
A water is being produced.
The limewater will change from clear to:
A pink
B blue
C dark
D cloudy
D cloudy
How can anhydrous copper sulfate be used as an alternative test for water in the combustion of a hydrocarbon fuel?
Collect the gas from combustion and cool it to condense water. Add the liquid to white anhydrous copper sulfate. If water is present, it will turn blue.
Explain how the combustion of fossil fuels can cause acid rain.
Many of the gases released by fossil fuel combustion are acidic so when They dissolve in the clouds they make the rain more acidic than normal
Explain how carbon monoxide is produced in a car engine.
Carbon in hydrocarbon fuel reacts with oxygen
from air but there isn’t enough of it for it all to form
carbon dioxide so it then forms carbon monoxide
Explain how the amount of carbon monoxide released into the air from a car exhaust can
be reduced.
by using a catalytic converter on the exhaust because it converts carbon monoxide to carbon dioxide
Explain why the carbon dioxide produced from the combustion of fossil fuels is a problem
for the climate.
It is causing an increase in the greenhouse effect leading to global warming and climate change.
