What are the advantages of biodiesel?
Biodiesel offers several advantages as a biofuel. It contains higher hydrogen and oxygen and less carbon compared to fossil fuels. This composition improves the combustion of biodiesel and significantly reduces particulate emissions from unburnt carbon.
Another major advantage is that biodiesel can be directly used in regular diesel engines without making any changes or modifications to the engines. It can even be used in its pure form without blending it with fossil diesel, making it a convenient and practical alternative fuel.
Explanation
The answer draws directly from the textbook context which mentions two main advantages: (1) the chemical composition of biodiesel (higher H and O, less C) leads to better combustion and reduced particulate emissions, and (2) its compatibility with existing diesel engines without modifications. These two points are sufficient for a 2-mark question. The context also mentions that biodiesel can be used in pure form, which adds practical value as an advantage.