What kind of reaction releases energy to the surroundings?
Endothermic
Reversible
Exothermic
Chemical cells produce a voltage. When do they stop producing a voltage and 'go flat'?
When one of the reactants has run out
When the cell becomes too hot
When the cell has been in use for a set time
What is the only chemical product when hydrogen and oxygen are reacted together in a fuel cell?
Water
Electricity
Carbon dioxide
Which is not an advantage for using a hydrogen-oxygen fuel cell in a space station?
No moving parts
Small and compact size
They generate useful heat for warmth
Where can hydrogen be obtained from on the space station without transporting it from Earth?
From plants
From water
From the Moon
Hydrogen can be used as a fuel for cars. Which of the following is an advantage of using hydrogen instead of petrol?
It is cheaper
Exhaust gases contain only water
It is easier to store
Which of the following is a disadvantage of using hydrogen as a fuel?
There are currently very few hydrogen filling stations in the UK
It directly contributes to global warming
It uses up finite fossil fuel resources
In addition to a fuel, what other chemical is needed by a fuel cell?
Nitrogen
Oxygen
Methane
In the space station, why can you not rely on solar cells all the time?
They have to be shut down for maintenance
They are unreliable and frequently overheat
They only produce electricity when the Sun is visible
Which of these equations represents the chemical reaction that occurs in a hydrogen-oxygen fuel cell?
hydrogen + oxygen → water
water → hydrogen + oxygen
acid → hydrogen + oxygen