LEADED AND UNLEADED PETROL
(1.) LEADED PETROL :-- In this type , Petrol is treated
with a lead compound i.e Tetraethyl Lead ( C8 H20 Pb) to reduce knocking ( problem due to unburn fuel ) problems in the vehicle.
But combustion of leaded petrol releases Lead into the air where it causes lead poisoning.
That is why Lead in petrol is banned in U.S.
(2.) UNLEADED PETROL :-- In this type of petrol leaded compounds are not used.
This type of petrol is mostly used.