Petrol by definition is millions of years old, says Naked Scientist Chris Smith.
Asked if it has an expiration date, Smith explains the science behind the substance and what could affect its longevity.
When we take that crude oil out of the ground by drilling a hole and feed that crude oil into a refinery, you split that crude oil up and make certain combinations of those fractions to make petrol so what is in the petrol is already millions of years old, but the blend that goes into the petrol that give it its characteristics, those things are going to be a unique combination...— Chris Smith, Naked Scientist
If you leave petrol in a sealed environment it chemically wouldn't change but obviously, you can't do that because it expands and contracts so you have to have a vented container for your petrol. That means some of the fractions will overtime evaporate from the petrol mix...— Chris Smith, Naked Scientist
So old petrol, unless it has been in a genuinely sealed environment with no prospect to escape, which would be unsafe, old petrol is not going to be good as fresh petrol. It's better to always have fresh petrol if you can.— Chris Smith, Naked Scientist
Click on the link below to hear more from Smith...