Carbon dioxide (chemical formula CO2) is an acidic colorless gas with a density about 53% higher than that of dry air. Carbon dioxide molecules consist of a carbon atom covalently double bonded to two oxygen atoms. It occurs naturally in Earth's atmosphere as a trace gas. The current concentration is about 0.04% (412 ppm) by volume, having risen from pre-industrial levels of 280 ppm. Natural sources include volcanoes, hot springs and geysers, and it is freed from carbonate rocks by dissolution in water and acids. Because carbon dioxide is soluble in water, it occurs naturally in groundwater, rivers and lakes, ice caps, glaciers and seawater. It is present in deposits of petroleum and natural gas. Carbon dioxide has a sharp and acidic odor and generates the taste of soda water in the mouth. However, at normally encountered concentrations it is odorless.As the source of available carbon in the carbon cycle, atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena. Plants, algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water, with oxygen produced as a waste product. CO2 is produced by all aerobic organisms when they metabolize organic compounds to produce energy by respiration. For instance, plants use it to produce carbohydrates in a process called photosynthesis. Since humans and animals depend on plants for food, photosynthesis, and therefore CO2, is necessary for the survival of life on earth.
It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals, including humans. Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread, beer and wine making. It is produced by combustion of wood, peat and other organic materials and fossil fuels such as coal, petroleum and natural gas. It is an unwanted byproduct in many large scale oxidation processes, for example, in the production of acrylic acid (over 5 million tons/year).It is a versatile industrial material, used, for example, as an inert gas in welding and fire extinguishers, as a pressurizing gas in air guns and oil recovery, as a chemical feedstock and as a supercritical fluid solvent in decaffeination of coffee and supercritical drying. It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence. The frozen solid form of CO2, known as dry ice is used as a refrigerant and as an abrasive in dry-ice blasting. It is a feedstock for the synthesis of fuels and chemicals.Carbon dioxide is the most significant long-lived greenhouse gas in Earth's atmosphere. Since the Industrial Revolution anthropogenic emissions – primarily from use of fossil fuels and deforestation – have rapidly increased its concentration in the atmosphere, leading to global warming. Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid.
Homework Statement
50cm^3 of a mixture of CO, CO2 and H2 were exploded with 25.0cm^3 of O2. After explosion, the volume measured at r.t.p. was 37.0 cm^3. After treatment with aqueous KOH, the volume was reduced to 5.0cm^3. Calculate the % composition by volume of the original mixture...
Its common knowledge that infra red radiation heats up an absorbing solid surface.
That is,the em radiation energy is converted into translational KE of the particles of the solid.
What happens in the case of an isolated CO2 molecules absorption?
Can the EM energy be converted into increased...
I have decided to do away with the template; all calculations have been done, I'm just having trouble interpreting the results.
An experiment was performed using a calorimeter and warm water. The data collected gave the following values for heat of fusion for ice, and heat of sublimation of dry...
Hello folks - I hope this is the right area to post...
I brew beer at home, and air, more correctly, the O2 in air causes oxidation and ruins beer. In order to prevent it, many home brewers use stainless steel containers that can be pressurised with CO2.
The commonly accepted wisdom is that a...
Hi there,
i'm trying to do molecular dynamics simulations with CO2. However, I'm running into some problems, that I don't fully understand up to know.
From a naive point of view, I would describe CO2 as a linear molecule consisting of 2 C-atoms and 1 O-atom.
To simulate a flexible model...
With the evolution of Advanced MEMS based CO2 sensors,Seeking some guidelines/suggestions to understand the various types(& techniks) of CO2 gas measurement methods(hence of sensor principles) and of Automatic or contemporary Gas Analyzers (for impurities) of CO2 Gas samples or of any Gaseous...
I am currently under the impression that the Oceans act like a big sponge. They absorb CO2. However when the temperature rises it releases that CO2.
Most reports give a rise of about 1 degree over the last half century.
I am also aware that the ocean floor is littered with volcanoes, sea...
Homework Statement
I'm in a class where we want to figure how liquid CO2 can be produced, how to store it, uses for it. Does anyone know any references online that might provide some information for this?
Homework Equations
The Attempt at a Solution
The conditions to produce...
Hi...
As many probably know, there is about to be a climate meeting in Denmark within 2 months, where they will discuss the climate. And some people wants the world to spent a lot of money reducing the CO2 from humans, which is a lot of money !
But has it been proved that CO2 is that bad...
Might one have a warming planet, without CO2 increase? The last 15,000 years is evidence for such case, since pre-industrial CO2 is considered as ~280. If one had a slow down in vertical mixing (i.e. lower surface water turnover; say 1% over 100 yrs for 15,000 yrs- giving 150%), resulting...
I've changed the numbers a bit so things work out a little easier
Homework Statement
The combustion of propane in a BBQ follows the balanced chemical reaction:
C3H8 + 5 O2 ---> 3 CO2 + 4 H2O
As this reaction occurs, approximatley 3000J of heat is released. If a roast takes approx...
Homework Statement
The total mass of C contained in all fossil fuels burned from 1750 to 2000 is estimated
as 2.77 x 1014 kg C. The amount of C released as CO2 from agricultural expansion and
deforestation during the same period is estimated as 1.31 x 1014 kg C. The concentration
of CO2...
I have been reading through some of the older papers concerning CO2 levels in the 20th and century, CO2 residence times, and the carbon cycle. (The papers this linked to article and paper are referencing. Another source is the 2300 papers Ian Plimer references in his book Heaven and Earth.) What...
Homework Statement
Gasoline consists primarily of octane, C8H18
Calculate the mass of CO2 produced from the complete combustion of 3.79 L (1.00 gallon) of gasoline (assume octane, density = 0.756 g/mL) with excess O2
The Attempt at a Solution
The balanced chemical formula would be:
2C8H18 +...
Does anyone know why you can see the smoke coming from dry ice? Is it actually CO2? It does not make sense to me, why could I see CO2 evaporating, but I cannot see it normally? Is it the moisture in the air that I can see reacting with the cold CO2?
I was reading a new paper titled "Impacts of Climate Change on Marine Organisms and Ecosystems" when I came across this statement:
It has been suggested that a CO2[atm] of 450 ppm is a critical threshold beyond which catastrophic and irreversible change might occur [7] this would bring a...
Homework Statement
Hi there, could anyone help me pls. I want to show my sons kinder class what happens when you put Dry Ice (solid CO2) into water but would like to know for them and for me what the actual process is when it sublimates. I don't understand why there are so many bubbles or...
I've been looking at phase diagrams and vapour pressure tables for CO2 and i notice that the data stops at the critical point. what would happen to the pressure of CO2 if I heated it to above the critical temperature and kept the volume constant? Would the pressure increase following the...
ok so it has been a few years since I have worked on things like this and I am needing some help
I have a CO2 tank that weighs 22.17 oz's when full. There is 9 oz's of CO2 in the tank. The problem I am working on is that I need to find out how far the tank will go when the safety burst...
McLean, J. D., C. R. de Freitas, and R. M. Carter (2009), Influence of the Southern Oscillation on tropospheric temperature, J. Geophys. Res., 114, D14104, doi:10.1029/2008JD011637.
http://www.agu.org/pubs/crossref/2009/2008JD011637.shtml
From the abstract:
Change in SOI accounts for...
What decision to make?
http://thehill.com/leading-the-news/dem-centrists-press-pelosi--to-shelve-climate-change-bill-2009-05-06.html
James Hansen, NASA climatologist has an outspoken opinion about cap and trade:
Temple of doom
So what would save more lives? reforming health care or...
I recently came across several apparently reputable sources (e.g., NASA, PBS) that describe a simple, elegant experiment intended to demonstrate carbon dioxide's role as a greenhouse gas. Each of them involves two sealed containers with thermometers - one containing air, the other containing...
Homework Statement
I need to calculate the mass of CO2 in a mixture where there is 1.5kg of N2 and 1kg of O2 present. The total pressure of the mixture is 1.5bar, the volume is 2m^3 and the temperature is 293K. I also know the cv values for the constituents.
Homework Equations
I...
There is an unexplained mystery as to why atmosphere CO2 levels varies long term (geologically) and short term (glacial/interglacial cycle.)
Contrary to what is repeated in many blogs the glacial/interglacial cycle changes of about 90ppm to 100 ppm is not due to colder oceans being able to hold...
In another thread (see msg #17 of "Only dirty coal can save the Earth"), user Bystander suggested I lay out more carefully for critical examination the physical basis for the impact of CO2 on climate, so that the assumptions can be seen clearly. This is an excellent idea, and here is my attempt...
http://icecap.us/images/uploads/TomQuirkSourcesandSinksofCO2_FINAL.pdf" is a paper published in Energy and Environment that claims the rise in CO2 is not from the combustion of fossil fuels.
I am in the process of reading it now and thought I would share it here.
The first thing that...
Came across a 2007 study concerning climate sensitivity.
It was published by the Journal Nature, but only as a letter.
Can't say exactly why they do that, but it probably hasn't
been scrutinized as closely as it would be otherwise. Anyhow,
in this study, atmospheric CO2 concentrations over...
ok for school, i am having to make CO2 cars...here is some information about it
http://en.wikipedia.org/wiki/CO2_Dragster
well anyway, i need to make the fastest one...(kinda of to help my grade xD) well i was wondering what the best design is for it...
the specifications i must have...
Homework Statement
Use the same device to separate singly charged CO2 having 12C and 14C. What are the radii of curvature?
This is a follow up question based on a HW problem I answered last week. The original problem was this:
A doubly charged helium atom is accelerated by a voltage 2700V...
G. Gerlich, R. D. Tscheuschner (2009) Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics. International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364 (World Scientific Publishing Co.)
see...
What is an optimal CO2 concentration (a range of values or percentages) for maintaining baseline performance among humans? For example, short term exposure to CO2 concentrations less than 5% has negligible impacts on performance (I don't think this is true, it's just an example). If anyone...
I'm not sure under which section this should go, but the application is engineering. I have a calibration problem that I'm trying to figure out:
I have a digital flowmeter that measures the flowrate of air and gives a SL/min (litres/minute at stansard conditions) value. The thing is I want to...
Is it possible to test the CO2 pressure in a soda bottle as simple science project that can be done at home? What kind of apparatus is need? The original goal is to test if CO2 pressure changes at different temperatures. It would be helpful if anybody had any suggestions on how to go about...
Okay guys, i have a significant amount of CO2 i can release into the atmosphere, how much will you pay me not to.
PS, there is no way you will find me.
i am new at this forum . and i don't know rules. and i know little english so i don t understand something so sorry.
i have one question. i wonder answer . 'cuz i think thing. but i don't find answer. i ask teacher. he told but i didnt understand. but i m sure my teacher doesn't know answer...
I found this article: http://www.sciencedaily.com/releases/2008/09/080929123941.htm and it talks about a machine that absorbs CO2 invented by a professor from University of Calgary.
I'm thinking to make a feasible model of it for construction (it's actually a school project), but the machine...
The number of stomata on leafs (breathing pores) of certain plant species appears to be sensitive to the CO2 level in the atmosphere. If it is higher, it appears that these plants does not bother to make many stomata, whereas CO2 is scarce, it simply makes more stomata to extract the CO2 from...
http://www.informaworld.com/smpp/content~content=a788582859~db=all
G. V. CHILINGAR, L. F. KHILYUK, and O. G. SOROKHTIN, 2008, Cooling of Atmosphere Due to CO2 Emission, Energy Sources, Part A, 30:1–9, 2008 ISSN: 1556-7036 print/1556-7230 online DOI: 10.1080/15567030701568727
Heads...
Hi all, i have been assigned to study indoor air quality and car cabin air quality project.
My Problem is:
How to measure Carbon Dioxide concentration in that constant volume of air? (consider there will be changes in the concentration and i need to quantify or contrast it at least.)...
Hi,
Could you please confirm these estimations for me:
Knowing that the Energy of Combustion of CH4 is 50.1 KJ/Kg, and that the specific heat for the CO2 at 273.15 K is approximately 0.81 KJ/Kg*K; please, could you confirm that in order to increase the temperature of 1 liter of gas of CO2...
I'm trying to determine the feasibility of a project, but have not yet taken fluid dynamics (next quarter).
I'm trying to figure out how much power could be produced with a CO2 powered turbine. The turbine will be activated for only a few seconds at a time, with speeds under power ranging...
If CO2 produced by industry is causing global warming then wouldn't there be hotspots above major industrial sites where the CO2 is most concentrated?
And wherever in the world CO2 is washed out of the air by heavy rainfall, shouldn't there be CO2 coldspots too?
If CO2 warming is increasing...
can anyone tell me what the saturation point of CO2 is in the atmosphere in relationship to it's effect as a green house gas? At what point does extra CO2 have no more effect?