Battery Passport 2027

Page 3 - Passionate about caravans & motorhome? Join our community to share that passion with a global audience!
Jul 18, 2017
13,065
3,712
32,935
Visit site
This is a serious question and I am not trying to be a smart R's but.........

How can a litre of fuel, that as a liquid, weighs around (or in the case of petrol less than) a kilogram, when burnt produce over 2kg of a gas?, Seems somewhat counter intuitive to me.

like I said, this is meant as a serious question not anything snarky.,
Somehow I doubt if you will get an answer as the greens or government make it up as they go along depending how much they would like to tax you. :ROFLMAO:
 
  • Like
Reactions: Mr Plodd
Nov 6, 2005
7,577
2,229
30,935
Visit site
This is a serious question and I am not trying to be a smart R's but.........

How can a litre of fuel, that as a liquid, weighs around (or in the case of petrol less than) a kilogram, when burnt produce over 2kg of a gas?, Seems somewhat counter intuitive to me.

like I said, this is meant as a serious question not anything snarky.,
I agree with questioning the statement - a litre of petrol/diesel weighs about 0.8 kg - but I guess the Hydrogen and Carbon in the fuel combines with the Nitrogen and Oxygen in the air and produces Carbon Dioxide as a by-product.
 
Nov 11, 2009
21,070
6,637
50,935
Visit site
This is a serious question and I am not trying to be a smart R's but.........

How can a litre of fuel, that as a liquid, weighs around (or in the case of petrol less than) a kilogram, when burnt produce over 2kg of a gas?, Seems somewhat counter intuitive to me.

like I said, this is meant as a serious question not anything snarky.,
It’s because it has to combine with oxygen in order to combust.

 
Last edited:
Nov 30, 2022
1,101
922
1,435
Visit site
It’s because it has to combine with oxygen in order to combust.


Can you provide a link to the science explaning that?

Oxygen and hydrogen combine to make water. So how much "weight" of each is required to make a kilogram of water?
If I split a kilogram of water into hydrogen and oxygen do the two products together weigh less than a kilo?,
I appreciate that hydrogen is lighter than oxygen, but it still has a weight.
 
Nov 11, 2009
21,070
6,637
50,935
Visit site
Can you provide a link to the science explaning that?

Oxygen and hydrogen combine to make water. So how much "weight" of each is required to make a kilogram of water?
If I split a kilogram of water into hydrogen and oxygen do the two products together weigh less than a kilo?,
I appreciate that hydrogen is lighter than oxygen, but it still has a weight.
No I cannot but I’m sure if you search on the internet you will find one. It’s 62 years since I gained my GCE O level in chemistry and memory isn’t what it was regarding molecular chemistry. 😂
 
Jul 23, 2021
709
627
2,135
Visit site
No I cannot but I’m sure if you search on the internet you will find one. It’s 62 years since I gained my GCE O level in chemistry and memory isn’t what it was regarding molecular chemistry. 😂
Can you provide a link to the science explaning that?

Oxygen and hydrogen combine to make water. So how much "weight" of each is required to make a kilogram of water?
If I split a kilogram of water into hydrogen and oxygen do the two products together weigh less than a kilo?,
I appreciate that hydrogen is lighter than oxygen, but it still has a weight.
The chemical formula for the combustion of petrol is as follows.

2 C 8H 18 + 25 O 2 → 16 CO 2 + 18 H 2O

Each atom has an atomic mass (you can look it up on the periodic table)
C = 12
H = 1
O = 16


EDIT * I messed up the maths.

So one molecule of petrol weighs 114 atomic mass units. One molecule of O2 weighs 32 units.

When you burn 2 of those units (total atomic mass of 228) with 25 O2 molecules (800 units) you produce 16xCO2 (44 units x 16 = 704 ) and 18 H2O (18 x 18 = 324).

Scale that up so you have some appropriate mass of petrol, and you can see that when burned, the resulting CO2 weighs more than the original petrol because of all the added Oxygen.
 
Last edited:
Jul 23, 2021
709
627
2,135
Visit site
I am sure that depleted nuclear fuel rods cannot be recycled and that is used to help charge EVs?
That depends on the type of reactor. But nuclear fuel produces no CO2 emissions.

BTW I am not a huge fan of nuclear, though I accept it is cleaner (from a CO2 perspective) than fossil fuels.
 
Jul 18, 2017
13,065
3,712
32,935
Visit site
The chemical formula for the combustion of petrol is as follows.

2 C 8H 18 + 25 O 2 → 16 CO 2 + 18 H 2O

Each atom has an atomic mass (you can look it up on the periodic table)
C = 12
H = 1
O = 16

So one molecule of petrol weighs 32 atomic mass units. One molecule of O2 weighs 32 units.

When you burn 18 of those units (total atomic mass of 576) with 25 O2 molecules (800 units) you produce 16xCO2 (44 units x 16 = 704 ) and 18 H2O (18 x 18 = 324).

Scale that up so you have some appropriate mass of petrol, and you can see that when burned, the resulting CO2 weighs more than the original petrol because of all the added Oxygen.
I still find that extremely hard to believe. We should all be dead with all that weight on us? Sounds like a load of codswallop by some scientists trying to keep their job and inflated salary. Who came up with that idea? A government employee? Probably why I weigh so much now Oh dear. LOL! :ROFLMAO: :ROFLMAO: :ROFLMAO:
 
  • Like
Reactions: Mr Plodd
Jul 18, 2017
13,065
3,712
32,935
Visit site
That depends on the type of reactor. But nuclear fuel produces no CO2 emissions.

BTW I am not a huge fan of nuclear, though I accept it is cleaner (from a CO2 perspective) than fossil fuels.
The depleted rods create more pollution that issues with CO2 as CO2w is necessary for human life on this planet. Now if we didn't have all these EVs pinching electric we wouldn't need more nuclear stations. LOL! :ROFLMAO:

Just kidding as know that unfortunately for some unknown reason you are big EV fan and being a cheapskate I am a big diesel fan! I love my big V8s and wish I could afford one. :cry:
 
Nov 30, 2022
1,101
922
1,435
Visit site
The chemical formula for the combustion of petrol is as follows.

2 C 8H 18 + 25 O 2 → 16 CO 2 + 18 H 2O

Each atom has an atomic mass (you can look it up on the periodic table)
C = 12
H = 1
O = 16


EDIT * I messed up the maths.

So one molecule of petrol weighs 114 atomic mass units. One molecule of O2 weighs 32 units.

When you burn 2 of those units (total atomic mass of 228) with 25 O2 molecules (800 units) you produce 16xCO2 (44 units x 16 = 704 ) and 18 H2O (18 x 18 = 324).

Scale that up so you have some appropriate mass of petrol, and you can see that when burned, the resulting CO2 weighs more than the original petrol because of all the added Oxygen.

Mr Gumby, Mr Gumby, My brain hurts!

Monty Python fans will understand :giggle:
 
  • Haha
Reactions: Buckman
Jul 23, 2021
709
627
2,135
Visit site
I still find that extremely hard to believe. We should all be dead with all that weight on us? Sounds like a load of codswallop by some scientists trying to keep their job and inflated salary. Who came up with that idea? A government employee? Probably why I weigh so much now Oh dear. LOL! :ROFLMAO: :ROFLMAO: :ROFLMAO:
Fortunately the laws of physics and chemistry don't require belief in order to operate. This is a pretty simple chemical reaction, and is something that would be covered by any 15-16 year old science or chemistry GGSE student .
 
  • Like
Reactions: otherclive
Nov 30, 2022
1,101
922
1,435
Visit site
Fortunately the laws of physics and chemistry don't require belief in order to operate. This is a pretty simple chemical reaction, and is something that would be covered by any 15-16 year old science or chemistry GGSE student .

Offering an explanation is commendable, but being patronising isnt!
 
  • Like
Reactions: Buckman

Sam Vimes

Moderator
Sep 7, 2020
1,804
1,347
5,935
Visit site
An easier explanation is that the combustion process that produces the CO2 requires Carbon, which is locked in the fuel type, and Oxygen, which might be supplied by the surrounding air.

So you may be using 1l of petrol, diesel, coal or whatever but also a lot more oxygen from the air is added to the process.
 
  • Like
Reactions: ProfJohnL
Jul 23, 2021
709
627
2,135
Visit site
Offering an explanation is commendable, but being patronising isnt!
Condescension is forbidden, but being dismissed as "codswallop to keep their job and inflated salary " and "made up by a government employee" is not? I am just asking what the rules are about ridicule...
 
Jul 23, 2021
709
627
2,135
Visit site
Only when burnt as fuel - when oil products are used for lubrication or chemical processes, industry is continually finding new ways to recycle those products.
Agreed. And fortunately, those uses are not concerning to climate change, as they don't result in CO2.
 
  • Like
Reactions: otherclive

Sam Vimes

Moderator
Sep 7, 2020
1,804
1,347
5,935
Visit site
Just as an aside.....

My car has done approx 56,000 miles on diesel. This means I've generated about 150,000 kg of CO2.

To date my Stop Start function has supposedly saved 0.8kg of CO2. Is it worth it?

Of course multiply that by a few million cars and it does add up.
 
Nov 6, 2005
7,577
2,229
30,935
Visit site
Just as an aside.....

My car has done approx 56,000 miles on diesel. This means I've generated about 150,000 kg of CO2.

To date my Stop Start function has supposedly saved 0.8kg of CO2. Is it worth it?

Of course multiply that by a few million cars and it does add up.
Are you sure that's the correct arithmetic? That's 90,123 km - my car produces 174 g/km which would only give 15,681 kg of CO2 so yours should be way under that.
 
  • Like
Reactions: Tobes

TRENDING THREADS

Latest posts