# How do they weigh co2

Discussion in 'Motorhome Chat' started by chaser, Aug 10, 2014.

1. ### chaserFunster

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I know there is another thread going about lez but thought this would get lost among that but how do they weigh co2 can you weigh smoke, and how do they get it to weigh more than it weighed in the first place, always been beyond me, serious question not taking the p

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3. ### PhilandMenaFunster

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4. ### hilldwellerFunsterLife Member

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Same way as you would weigh anything. Put it on a scale.

Take a jar, pump all gas out with a vacuum pump.
Weigh it = T
Fill jar with any gas.
Weigh it G

G - T = gas weight.

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6. ### chaserFunster

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Yes , but how do you get tons of stuff out of something that floats away, like a car exhaust how can you get tons out when you have only put lbs in and used most of it to drive the engine

7. ### hilldwellerFunsterLife Member

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I don't think you get tonnes out of a single car exhaust but out of 10,000,000 cars you'll get a lot.

Look up. All those clouds contain many tonnes of water !

8. ### John LaidlerFunster

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You don't get tons out of a single car engine in a short time but you do out of millions of cars.
The calculation is quite easy. Tests will show what mix of gases come out of a car exhaust for say every kg of fuel used. Then multiply this by how much fuel is being sold over a year and you have a pretty good idea how much of various gases are released into the atmosphere. It is a lot! But of course there are other factors to complicate things, absorption of CO2 by plants, effect of sunlight on molecules, effect of sea water etc. Tis complicated which is why there is still an argument about climate change.

9. ### MattyjwrFunsterLife Member

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Everything is made of atoms - like Lego bricks, they are the building blocks of the universe. The oxygen that we breath is generally made up of two atoms of oxygen (given the symbol O2). Each atom has a weight (known as the atomic mass which is the weight in grams per mole) and oxygen is approx. 16. Therefore, the oxygen that we breath has an atomic mass of 16 x 2 = 32. Carbon dioxide has the formula CO2 - hence it will have the atomic mass (or more correctly, molecular mass because it is made up of two different types of atoms) of two oxygens (32) plus a carbon atom (approx. 12), giving a total of 44. It is, therefore, heavier than oxygen. The gas used in the supposed theft was reported to be Carbon monoxide (CO) which would have an atomic mass of 12 for the carbon and 14 for the oxygen = 26 - making it slightly less dense, or lighter than oxygen.

Weighing smoke would need you to identify the atoms in the smoke and the density - not easy because there are so many possible combinations. However, the key thing to look for as a motorhomer, are the atoms that are combined together as compounds that could cause damage to people. Eg. When you burn cooker gas in your van, the products are carbon dioxide (CO2) and water (H2O) (hence some dampness in the air when cooking with gas) - neither of which would kill you. A poorly maintained gas stove may also have carbon monoxide produced - a similar density to oxygen and is dangerous because it sticks to your red blood cells and stops your body getting enough oxygen; it can result in death.

Last edited: Aug 10, 2014
10. ### pappajohnFunsterLife Member

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That went over my head so fast it blew my hat off........

11. ### John LaidlerFunster

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I am not sure this heavier/lighter than air argument is significant. Air is made up of a number of gases and they don't sit in the atmosphere in distinct layers with say the heaviest gas at ankle hight and a slightly lighter gas level with your knees. The gases spread by diffusion but in a confined space like a MH convection currents play a strong part and even a heavy gas could be swept up to the ceiling by the heat from a cooker or even the back of a fridge until diffusion spread the gas throughout the space.

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13. ### JJFunster

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I don't know how they weigh CO2 but they weigh pies over the rainbow...

"Somewhere over the rainbow,

Weigh a pie..."

JJ

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