Gas and Diesel are both extractions of crude oil. Both are used for a lot of things. They are used as engine fuel, and they can be used in generating power, and also, they are used for both industrial and domestic purpose. However, there are some differences between Gas and Diesel.
Chemically, the structural formula for gases is quite different from the structural formula for Diesel. Gases are pure size hydrocarbons. They are mostly the few first members of hydrocarbons series. Diesel, on the other hand, is a high carbon organic compound. They are found as the homologous series is projecting forward.
Due to the nature of Diesel and its compositions, it takes a while for it to be burned entirely unlike gas. Spark plugs are needed in cars with gasoline engines to provide power for the car, while, cars with diesel engines do not need spark plugs.