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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.
Answer
One advantage of using a hydrogen-oxygen fuel cell is that it produces a voltage as long as hydrogen and oxygen are supplied, providing a longer lifetime compared to chemical cells, which may degrade over time or contain harmful/toxic substances that require careful disposal.
Step 2
Step 3
Calculate the volume of 48g of oxygen at room temperature and pressure.
Answer
To calculate the volume of 48g of oxygen:
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Determine the moles of oxygen: [ \text{moles of } O_2 = \frac{48 \text{ g}}{32 \text{ g/mol}} = 1.5 \text{ mol} ]
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Use the fact that 1 mol of gas occupies 24 dm³: [ \text{Volume} = 1.5 \text{ mol} \times 24 \text{ dm}^3/ ext{mol} = 36 \text{ dm}^3 ]
Thus, the volume of oxygen is 36 dm³.