Carbon dioxide is measured in tons?

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I was watching Discovery Channel last night about the environment and global warming. I'm not too interested in environmental concerns but the program caught my attention. They were pointing out that carbon dioxide emissions from gasoline-burning cars emits tons of carbon dioxide into the atmosphere, greatly contributing to the greenhouse and global warming. Carbon dioxide has weight? It can be weighed? I thought it was a lighter-than-air gas and had little if any "weight" at all. I simply do not understand what is meant by "weight" associated with carbon dioxide. So how would carbon dioxide actually be measured to determine a carbon footprint? With a scale? How can you weigh a gas? How can you measure or weigh a gas that's being emitted from your tailpipe?

I know some of you are thinking this is the dumbest question they have ever seen on the Internet and that I must be incredibly ignorant with regard to environmental concerns -- I confess! I am indeed. I've never bothered to research environmental concerns very much, but now it's getting my attention (Al Gore would be proud of me). I've always thought of environmentalists as a bunch of liberal, hippie activists using scare tactics to get people to pay more taxes for protection against global warming. However, I am convinced global warming is for real -- the undeniable evidence is there for all to see. However, I'm not convinced that mankind has much to do with it. I think it's a naturally occurring cyclical thing and there's not much can be done it.

The program was suggesting alternative sources of energy other than fossil fuels which spew "tons" of carbon dioxide into the atmosphere. Some of them were:

Wind power but it obviously takes millions of tons of fossil fuels to manufacture all those huge windmills?

Solar panels? Takes a lot of fossil fuels to make 'em.

Electric plug-in-to-your-wall cars to charge batteries? Where do they think electricity in you home comes from? It has to be produced usually by coal-fired generators.

Ethanol? Just fine in Brazil where they have space to grow a zillion acres of sugar cane. But not in America where agricultural space is limited. And corn doesn't produce as much bang for the buck as sugarcane. Brazil and other tropical and semi-tropical nations have begun to export ethanol and are cutting down all the rain forests to grow more sugarcane. Isn't this self-defeating?

The program pointed out that nuclear energy is safe and leaves no carbon footprint whatsoever. So why doesn't America just go nuclear? 80 percent of the nation's energy demands could be supplied with more nuclear power plants. The other 20 percent could be supplied with America's own oil wells.

And then there's the issue of hydroelectric power which like nuclear power is totally clean and environmentally friendly. America has some mighty rivers that could accommodate a lot more hydroelectric power dams.

I've been some research about the environment on the net, but the whole issue is wacky and confusing to me. Thanks for any help.

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Measuring a gas is NOT an easy task. In researching the most popular search engine on Internet, I typed into Google, "how to weigh a gas" and came up with the following hyperlink. To see how gases are weighed, click here:

http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/weighgas.html

Some problems with gas measurement accuracy are noted here:

"Accurately weighing small quantities of flowing gas is a very difficult thing to do," Remenyik said. Most methods determine the weight of gas by measuring it on a balance that requires a long time to collect samples or by deriving it from equations relating temperature, volume and pressure. Measuring temperature, volume and pressure are indirect mass measurement methods that will have some errors that accumulate in the calculations."
>>>
"...Also, balances that can measure 50- to 100- pound objects, the weight range of most gas containers, cannot accurately measure a few tenths of an ounce of gas inside the container. Scientists usually must spend hours or days collecting gas heavy enough to be weighed. Chemical reactions and adsorption significantly reduce the accuracy of indirect methods that derive the gas weight. "

http://www.ornl.gov/info/press_releases/get_press_release.cfm?ReleaseNumber=mr19951009-00

Hydroelectric and nuclear power totally clean? Sometimes having a small carbon footprint is not the only environmental consideration.

Please rethink or research that better. Definitely wrong there on both counts. What do you think happens with spent nuclear fuel? The remnants stay around for thousands of years.

Hydroelectric projects can be disruptive to surrounding aquatic ecosystems. For instance, studies have shown that dams along the Atlantic and Pacific coasts of North America have reduced salmon populations by preventing access to spawning grounds upstream, even though most dams in salmon habitat have fish ladders installed.

Water exiting from turbines is typically much colder than the pre-dam water, which can change aquatic faunal populations, including endangered species.

Another disadvantage of hydroelectric dams is the need to relocate the people living where the reservoirs are planned.

Regarding wind power and others (such as solar): "Wind power but it obviously takes millions of tons of fossil fuels to manufacture all those huge windmills? "

The cost environmentally to mfr these windmills and solar panels is that it has a one-time effect. Whereas the cost for other less environmentally-friendly methods has a daily cumulative impact...damaging the environment over years and decades.

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Actually...

Calculating the weight of Carbon Dioxide that is being produced by a factory, car... etc. is not that difficult at all.

They know how much fuel they are burning (i.e. how much coal). They know how many carbon atoms are in this fuel (this is not difficult to find out). Thereforce they know how many carbon atoms there are in the fuel they are using.

Each carbon atom burned creates one molecule of carbon dioxide which has a very well known weight.

So you simply multiply the number of carbon dioxide molecules with the weight of a carbon dioxide molecule and you have a very accurate value for the weight of the gas.

The numbers given on these shows are generally accurate, and there is nothing complicated about them at all.

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So how do you explain the measurement methodology that I posted?

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To answer your other point...

Most forms of energy produce SOME carbon dioxide (and those that don't are very expensive or have some other problems).

The idea is to get the most usuable energy while creating the least about of Carbon Dioxide (and at a reasonable cost).

Wind power creates a large amount of energy (and it is true that there some cost to create the windmills) but this is a very small amount for the energy that is created. The problem with wind power is that is more expensive than fossil fuels.

Nuclear power also creates very little carbon dioxide. Of course it has other well known problems.

What makes this issue interesting (and complex) is that fossil fuels (oil and coal) create a lot of carbon dioxide but are very cheap compared to other energy source.

Currently it comes down to a tradeoff between how much money it costs to produce the energy... versus how much greenhouse gas it produces.

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All molecules have mass and therefore weight.

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Negative weight is also possible. Hydrogen rises because of buoyancy.
And a satellite has zero weight, although it has plenty of mass.

Currently, nuclear power has a major problem with safely storing the radioactive waste for a few hundred years.
Because a large storage facility like Yucca mountain is not ready yet, the nuclear waste is just piling up at the nuclear reactors with nowhere to go.

My biggest hope is for fusion energy, converting hydrogen into helium.
No radioactive waste, the fuel comes from water, no carbon involved.
Too bad it's still 40 years away.
THAT would be a worthwhile trillion-dollar "national mission"!

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I think it is a big stretch to say that hydrogen has negative weight. Sure, hydrogen rises when it is in the atmosphere because the force of buoyancy pushing it upward is greater than the force of gravity pulling it downward.

It seems like a stretch to say this affects its weight. Better to say that its weight is being countreracted by a separate force.

Consider a 2,000 lb boat. It floats in the water because the force of buoyancy pushing it upward equas the force of gravity pulling it downward.. It would seem strange to me to say the boat was weightless whenever it was floating in water.

There are two different meanings of the word "weight" which are interrelated in a confusing way that gives high school physics students (and their teachers) endless headaches.

The common use of weight measures the quantity of somthing-- for example when my wife tells me to get two pounds of chicken. The scientific meaning is the amount of force on any object due to gravity.

The confusion is that in all of our experience (except for the few of us who have been to space) these to measure are the same.

Scientists will, for example, tell you the weight of the Hubble Space telescope-- in pounds if you ask (try googling). NASA is even inconsistant, for Hubble (yes like a good nerd I just checked) saying "launch weight" for the Hubble (a good way as any to avoid the problem), but gladly giving the weight of its components.

Science teachers get pedantic about this. But, in reality, the answer that common "weight" and scientific "weight" should be treated as two separate definitions for two separate (although intertwined) concepts.

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ebrown_p wrote:

Actually...

Calculating the weight of Carbon Dioxide that is being produced by a factory, car... etc. is not that difficult at all.

I asked: "So how do you explain the measurement methodology that I posted? "

You dismissed the research that I provided the person who posted in an off-hand manner and didn't readdress it. Are you saying that what I researched is incorrect? Please explain

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Well Ragman,

There is a simple way to accurately make this calculation. That there is a more complex way to do it doesn't take away from the fact there is a simple way.

The "weight" of gasses are usually calculated-- not with a scale, but by knowing the properties of the gas. If I know the temperature, the volume and the pressure of a tank of helium, then I can very easily calculate the weight of helium inside because I know the properties of helium.

This is a typical problem that is given to high school physics or chemistry students. You may even remember PV = nRT which (as an former physics teacher) I am sure was one of the highlights of high school for you.

You can also use a scale to measure the weight of helium in a tank. The force of buoyancy in this case has to do only with the volume of the tank, and the density of air outside the tank-- so this is easy to account for.

The issues of finding an accurate enough scale is an issue now... especially if the helium in the tank is at low pressure-- but there are scales that are good enough (and expensive enough) to make a good measurment.

But it is much easier to just calulate this value using the pressure, volume and temperature.

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I'm 56...so high school physics was way too long ago. I do vaguely recall the formula now that you told me.

I just wanted to be sure that my info was not bogus. As the info is good, I feel validated.

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Matter has mass, not weight. Weight is a force resulting from acceleration of some form. Re Newtons second law, F=ma.

Hydrogen has mass, H2 is 2 g/gmole. Air is about 29g/gmole, and a gmole of an ideal gas at STP (1 atm pressure & 0 Celsius) is about 22.4 liters and H2 and air are pretty ideal at STP.

BTW CO2 has a molecular mass of 44 g/gmole--if you know the volume and the combustion reaction C yields a little over 3 grams CO2 for every g C burned.

Rap

Rap

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@Ragman,

This is unrelated to the question, but it could be the largest show of force from something tiny you will ever see. Run yourself a bath, and hop in it with a bottle full of water. Take the cap off the bottle, invert it, and put it in the bath (just the top of the bottle). You will notice that the water in the bottle, even though it is well above the level of the bath water, doesn't come out. Now slowly raise the bottle. The water only starts to escape the bottle the moment the bottle leaves the water completely.

How is this a show of force? How is that amazing? Disregarding the impossibility of such a feat, that bottle of water could weigh 100 trillion tonnes. And you could hold all that weight up with one cap full of water.

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@easyasabc,

easyasabc wrote:

They were pointing out that carbon dioxide emissions from gasoline-burning cars emits tons of carbon dioxide into the atmosphere, greatly contributing to the greenhouse and global warming............I thought it was a lighter-than-air gas and had little if any "weight" at all

.
CO2 should go down, not up.

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@ebrown p,

Thanks, ebrown - good explanation! Though it shouldn't be your wife's job to tell you to get the chicken. You should take more responsibility for household chores.

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Global CO2 emissions have never been higher. Hard to control those Chinese and Indians. Why haven't global temperatures budged in the last 16 years and the Arctic Ice cap growing 60% in last year? With concentrations of CO2 only 3 00 or 400 parts per million what would you expect? That is only 3 or 4 black marbles in 10,000 white marbles - you would be challenged to find them.

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@steve5skier,

Quote:

Global CO2 emissions have never been higher. Hard to control those Chinese and Indians. Why haven't global temperatures budged in the last 16 years and the Arctic Ice cap growing 60% in last year?

Please provide the source for global temperatures not budging in the last 16 years. The 16 year data shows a warming trend in surface temperatures if you do any standard regression.
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt

Picking 2 points in time doesn't show a trend. Comparing last year's ice which were the lowest ever recorded to this year's which was still lower than the norm doesn't prove anything about the ice. It does say a lot about you however.

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gases are composed of atoms, therefore they have weight, just think about a tank of compressed oxygen to help someone breath.

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@nazia08,

Here is a good way to visualize the weighing of a gas. First of all, you can't just set a scale in the middle of the room and try to read the weight of the air above it, right? That would be like setting a scale on the bottom of your swimming pool and expect to weigh the water above it. Not gonna happen. But you take that scale out of the pool and dip a container full of that same water and set it on the scale, you can read the weight (less the container of course).

So, to weigh a gas such as CO2, you pull a perfect vacuum on an emply jar, weigh it, now put as much CO2 into the jar as you can and weigh it again. It will weigh more than when it was emply, guaranteed!

Or, take a chunk of dry ice which is pure, highly compressed CO2 and set it on a scale. It will have weight that can be measured before it evaporates.

I ain't never been in space before but I recon I would love to go if given the opportunity.

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Hey, nice discussion, Thanks for sharing this useful information.

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Carbon dioxide is measured in tons?

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