Question Constellation Sign up for free AQA · GCSE · Chemistry · Higher
Hydrogen fuel environmental benefits
In the future, gas central heating boilers may burn hydrogen rather than natural gas. Table 2 shows information about these fuels when 1 dm³ of the fuel is burned in a central heating boiler.
| Hydrogen | Natural gas | |
|---|---|---|
| Energy released in kJ | 11.9 | 37.1 |
| Mass of carbon dioxide produced in grams | 0.00 | 1.83 |
| Mass of water vapour produced in grams | 0.75 | 1.50 |
| Mass of oxides of nitrogen produced in grams | 6.6 × 10⁻⁴ | 4.9 × 10⁻⁴ |
Explain one positive impact on the environment of burning hydrogen rather than natural gas as a fuel. Use Table 2.
Write your answer first. You can study the marking guidance whenever you need it.
Study the marking See what earns credit and compare it with a full-mark answer.
Marking points
- 1 States less climate change/global warming, or a valid effect of reduced climate change.
- 2 Uses Table 2 to link this to hydrogen producing no carbon dioxide.
Full-mark answer
Burning hydrogen would contribute less to climate change because Table 2 shows that it produces no carbon dioxide, whereas natural gas produces carbon dioxide.
Why this answer loses marks
Hydrogen is cleaner because it only makes water.
The table-based explanation must connect the absence of carbon dioxide to a reduced climate impact; water vapour is not the credited link.