Hydrogen-oxygen fuel cells, rather than chemical cells, can be used to power some vehicles - Edexcel - GCSE Chemistry - Question 8 - 2021 - Paper 1
Question 8
Hydrogen-oxygen fuel cells, rather than chemical cells, can be used to power some vehicles.
(a) Give one advantage of using a hydrogen-oxygen fuel cell, rather than... show full transcript
Worked Solution & Example Answer:Hydrogen-oxygen fuel cells, rather than chemical cells, can be used to power some vehicles - Edexcel - GCSE Chemistry - Question 8 - 2021 - Paper 1
Step 1
Give one advantage of using a hydrogen-oxygen fuel cell, rather than using a chemical cell, to power a vehicle.
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Answer
One advantage of hydrogen-oxygen fuel cells is that they produce a voltage as long as hydrogen and oxygen are supplied, and they do not produce harmful or toxic substances like chemical cells, which require careful disposal after use.
Step 2
Complete the half-equation for the reaction taking place at one of the electrodes in a hydrogen-oxygen fuel cell.
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Answer
The completed half-equation is:
ightarrow 2 ext{H}_2 ext{O}$$
Step 3
Calculate the volume of 48g of oxygen at room temperature and pressure.
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Answer
To calculate the volume of 48g of oxygen at room temperature and pressure:
First, determine the number of moles of oxygen:
extmolesofoxygen=16g/mol48g=3extmol
Next, use the molar volume of gas at room temperature and pressure, which is 24dm³ per mole: