Hydrogen v Petrol in Cars
Specification Point 8.14:
Evaluate the advantages and disadvantages of using hydrogen, rather than petrol, as a fuel in cars
- Hydrogen is used in rocket engines and in fuel cells to power some cars.
- It reacts with oxygen in an exothermic reaction:
2H2 + O2 →2H2O
- Hydrogen has a series of advantages and disadvantages regarding its use as a fuel:
- It releases more energy per kilogram than any other fuel (except for nuclear fuels).
- It does not pollute as it only produces water on combustion, no other product is formed.
- It is a renewable source and is extracted from water by electrolysis.
- Modern fuel cells are equipped to extract hydrogen from the same water they produce.
- Expensive to produce and requires energy for the production process.
- Difficult and dangerous to store and move around (usually stored as liquid hydrogen in highly pressurised containers).
Specification Point 8.15:
Recall that petrol, kerosene and diesel oil are non-renewable fossil fuels obtained from crude oil and methane is a non-renewable fossil fuel found in natural gas
- Non-renewable fossil fuels are obtained from crude oil by fractional distillation.
- Petrol is used as a fuel in cars, kerosene is used to fuel aircraft and diesel oil is used as a fuel in some cars, trucks and heavy vehicles such as tanks and trains.
- There are finite amounts of all three and they all contribute to pollution and global warming.
- Natural gas consists mainly of methane, CH4
- This is also a non-renewable fuel as there are finite reserves available.
Edexcel GCSE Chemistry Notes
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Morgan’s passion for the Periodic Table begun on his 10th birthday when he received his first Chemistry set. After studying the subject at university he went on to become a fully fledged Chemistry teacher, and now works in an international school in Madrid! In his spare time he helps create our fantastic resources to help you ace your exams.
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