Explanation:
We have a gas sample of carbon dioxide and we know its volume, the pressure and the temperature. We can find the number of moles of that sample using the ideal gas law.
P * V = n * R * T
Where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas law and T is the temperature.
R = 0.082 atm*L/(mol*K)
Since R is in atm*L/(mol*K) we have to convert the volume from mL to L, the temperature from °C to K and the pressure from torr to atm.
1000 mL = 1 L
V = 26 mL = 26 mL * 1 L/(1000 mL)
V = 0.026 L
760 torr = 1 atm
P = 623 torr = 623 torr * 1 atm/(760 torr)
P = 0.820 atm
T = (273.15 + 11 ) K
T = 284.15 K
Now we can replace these values in the formula and solve it for n to find the number of moles that are present in the sample.
P * V = n * R * T
n = P * V/(R * T)
n = 0.820 atm * 0.026 L/(0.082 atm*L/(mol*K) * 284.15 K)
n = 0.000915 mol
Finally we can convert the moles of the sample into grams using the molar mass of carbon dioxide.
molar mass of C = 12.01 g/mol
molar mass of O = 16.00 g/mol
molar mass of CO₂ = 1 * 12.01 g/mol + 2 * 16.00 g/mol
molar mass of CO₂ = 44.01 g/mol
mass of CO₂ = 0.000915 mol * 44.01 g/mo
mass of CO₂ = 0.040 g
Answer: There are 0.040 g of carbon dioxide in the sample.
The reaction represented by the following equation is a reversible process. N2O4(g)➡️⬅️2NO2(g)If you were to allow 1 mol of NO2 to react in a sealed container for some time, what would you expect to find in the container?NO2 onlyN2O4 onlyNothing, the vessel would be emptySome N2O4 and some NO2
Explanation:
The reaction:
N2O4(g) <=> 2NO2(g)
Inicially 0 [1 mol/Volume]
Reacts +x -2x
Equilibrium +x [1 mol/Volume]-2x
[1 mol/Volume] means molarity
In a chemical reaction, chemical equilibrium is the state in which the forward reaction rate and the reverse reaction rate are equal. The result of this equilibrium is that the concentrations of the reactants and the products do not change.
Therefore, the answer: Some N2O4 and some NO2
Define electronegativity.
A neutral atom has high electronegativity. Describe what happens to this atom during ionic bond formation.
No trolls, fake answers, copied answers
Electronegativity is defined as the ability of an element to accept electrons to its shell during a chemical reaction for the formation of a stable bond structure.
What is a neutral atom?A neutral atom is the atom that contains an equal amount of electrons and protons which means that is has a zero net charge. Example is sodium.
Electronegativity is defined as the ability of an element to accept electrons to its shell during a chemical reaction for the formation of a stable bond structure.
During ionic bond formation, the elements involved tries to obtain an octet structure by either donating or accepting electrons.
Alkali metals( such as the neutral element of sodium? have the lowest electronegativities, while halogens have the highest.
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What makes water a polar molecule? options:A) The equal forces between oxygen and hydrogenB) The liquid nature of waterC) The uneven bend in the bond between oxygen and hydrogenD) The ionic bond between oxygen and hydrogen
The polarity of a molecule is given by the difference in charges, hydrogen has a slightly positive charge and oxygen has a negative charge. Its electronegativity difference between hydrogen and oxygen is less than 1.7 making the bond a covalent bond.
That said, we can rule out options A and D. Now, the state of matter does not affect the polarity of the molecule, so option B will also be incorrect.
The correct option will be C, since there is a difference in charges that makes water polar.
Answer: C) The uneven bend in the bond between oxygen and hydrogen
What is the correct lewis structure for CO2?a) Ab) Bc) Cd) D
Of the options given, the correct one for the Lewis structure of CO₂ is option A.
In the covalent structure of CO₂, each atom will tend to have 8 electrons on its side, in order to comply with the octet rule. In this rule, an atom that has 8 electrons in its valence shell, will gain stability for having a noble gas electronic configuration.
Hence, the correct lewis structure for CO₂ is option A. In this configuration, each atom has 8 electrons on its side and all of them are neutral (the total charge of the molecule is zero). They all achieve the octet rule.
Although in option B all the atoms have 8 electrons (thus complying with the octet rule), in this configuration the oxygen atom on the left has a negative charge (-1) and the oxygen on the right side has a positive charge (+1). The total charge on the molecule is zero (it is neutral). In fact, this is a resonance structure of configuration A.
In option C, the total charge of the molecule is -2, so this is not a stable configuration. The number of electrons on carbon is wrong.
Finally, in option D the oxygen on the right side does not achieve the octet rule (it only has 6 electrons shared), and also the carbon atom has a charge of -2, and the oxygens have charges of -1 (left) and +3 (right), so this is not a stable configuration.
Therefore, the correct lewis structure for CO₂ is option A.
Define hydrogen bonding and explain how hydrogen are bonding involved in the
transfer of genetic material.
Answer:
Hydrogen bonding is a special type of dipole-dipole attraction between molecules, not a covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom.
Explanation:
The chemical reaction of hydrogen with oxygen produces water.
2H₂(g) + O₂(g) → 2H₂0 (g)
a. How many moles of O₂ are required to react with 2.6 moles of H₂?
b. How many moles of H₂ are needed to react with 5.0 moles of O₂?
Answer: a
explanation: Make a ratio of the number of moles and do the calculations. Do you get it?
What is the molarity of ions in a 0.561 M solution of Ca(OH)₂
assuming the compound dissociates completely?
For each particle (molecule) of Ca(OH)2 that was present, assuming full dissociation of the complex, you would get two particles (ions). CaO + H2O equals Ca(OH)2 (2 particles)
A 0.561 M solution contains 0.561 moles of Ca(OH)2 per kilogram of solvent. Ions' molality would be 2 x 0.561m = 1.122m.
How is an ion's molarity determined?The most used unit for expressing solution concentration is molarity (M), which is calculated by dividing the solute concentration in moles by the volume of the solution in liters: M stands for moles of solute per liter of solution.
What does ion molality mean?The kilograms of solvent divided by the moles of ions in the solution is the molality. As an illustration, if You will have 1.0 molal concentration of sodium chloride, for instance, if 1.0 moles of sodium chloride are dissolved in 1.0 kilogram of solution.
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What is the Organic compound shown? A) PropyneB) 1-ButeneC) 1-ButyneD) Acetylene
ANSWER
1-Butyne
STEP-BY-STEP EXPLANATION:
To name the below structure, we need to consider the following
0. The number of carbon atoms present in the structure
,1. The type of bond and the location
According to the structure given, we have four carbon atoms
These four carbon atoms mean Butane according to the alkane family
We have a tripple bond in between the first and second carbon atom
Since we have a tripple bond, the -ane in butane will be changed to -yne
Hence, the name of the structure is 1-Butyne
I need help with something please
Since both metals are in the same group in the periodic table and both non-metals are also in the same group in the periodic table, they have the same charge (metals = 1+; non-metals = 1-). So this makes the reaction easier for us:
NaCl + LiBr = LiCl + NaBr
What element has the most similar property as fluorine
Answer:
Chlorine and Bromine are also halogens so they are similar to fluorine
What is a quasar?
Two stars moving around each other.
A star that emits a repeated radio signal.
A star that emits intense radio and light energy.
A system of stars held together by gravity.
A collapsed star emitting no light.
A quasar is a star that emits intense radio and light energy.
A quasar is an extremely bright radio source. It is called a quasi-stellar radio source. It appears to be like a star but is not a star. These quasars are young galaxies that are located far away from us and are highly luminous. The luminosity of a quasar is 1000 times greater than the luminosity of a milky way galaxy.
A quasar is powered by a supermassive black hole with its mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc.
The quasars were first discovered in the 1950s using the Hubble space telescope and were found to be a massive bright source emitting radio waves of unknown origin. But now, millions of quasars were discovered.
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How many milliliters of 0.165 M HCL are needed to neutralize completely 25.0 mL of 0.101 M Ba(OH)2
We have a neutralization between the HCl (acid) and Ba(OH)2 (base):
To calculate the mL asked, we need to use the next formula:
M1 x V1 = M2 x V2 (1)
We assign number 1 to HCl and number 2 to Ba(OH)2
Remember: M molarity and V volume
-----------------
Data:
We know M1 = 0.165 M (HCl) and M2 = 0.101 M, V2 = 25.0 mL.
-----------------
Procedure:
We clear V1 from (1):
V1 = M2 x V2/M1 = 0.101 M x 25.0 mL/0.165 M = 15.3 mL
Answer: V1 = 15.3 mL
calculating formal charge
The carbonate ion has the simplest oxo carbon anion structure. One carbon atom is surrounded by three oxygen atoms in a trigonal planar arrangement, giving it D3h molecular symmetry. Its molecular mass is 60.01 g/ mol and its formal charge overall is HCO3.
Explain about the structure of carbonate ion?
Carbonate Organization its structure is a trigonal planar arrangement of three oxygen atoms surrounding a carbon atom. Two single bonds to the negative oxygen atom and two double bonds to the neutral oxygen atom make up the carbonate ion's Lewis structure.
The carbonate ion, a salt of carbonic acid, is the most basic form of the oxo carbon anion. A polyatomic ion, it has the chemical formula CO32-. The term "carbonate" can also refer to a carbonate ester, an organic molecule with the carbonate group C(=O)(O-)2.
The carbonate has a valency of two because it may combine with two hydrogen atoms.
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D
A student mixes a tablespoon of powdered lemonade into 8 ounces of
water. She weighs the powdered lemonade and the water separately.
After mixing, the student finds the weight of the combined mixture.
Which of the following will the student most likely observe about the
weight of the mixture?
A. The weight of the mixture will be less than the combined weight
of the powdered lemonade and the water.
B. The weight of the mixture will be the same as the combined
weight of the powdered lemonade and the water.
. C.The weight of the mixture will be more than the combined
weight of the powdered lemonade and the water.
. D. The weight of the mixture will be the average of the weight of
the powdered lemonade and the weight of the water.
●
●
The weight of the mixture will be the same as the combined
weight of the powdered lemonade and the water.
What is a mixture?The term mixture has to do with the combination of two or more substances that are not chemically combined together. We can see that due to the fact that substances that can be found in a mixture are not chemically combined together, then they can be separated by the means of physical methods.
We have to also bear in mind that mass can not be created nor destroyed but can be converted from one form to another. This implies that the total mass of the mixture must be the same as the sum of the masses of the individual components that are found in the mixture as this is in obedience to the law of the conservation of mass that have been detailed above in this answer.
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A 3.00 L sample of paint that has a density of 4.65 g/mL is found to contain 33.1 g lead (II) nitride. what is mass percentage of lead in the paint and what is the ppm?
Density relates the mass of a compound to its volume. We will first find the mass of the solution using the density and volume given. We have the following equation:
[tex]\rho=\text{ density = }\frac{Mass}{Volume}[/tex]We clear the mass,
[tex]\begin{gathered} Mass\text{ = }\rho\times Volume \\ Mass\text{ =}4.65\frac{g}{mL}\times3000mL \\ Mass\text{ =}13950\text{ g} \end{gathered}[/tex]So, the mass of paint is 13950 g. Now the mass percentage of the lead in the paint will be calculated as follows:
[tex]\begin{gathered} \%mass=\frac{\text{ Mass of lead (II) nitride}}{Mass\text{ of paint}}\times100 \\ \%mass=\frac{33.1\text{ g}}{13950\text{ g}}\times100 \\ \%mass=0.24\% \end{gathered}[/tex]The mass percentage of lead in the paint is 0.24%.
ppm concentration means the quantity of solute in milligrams (mg) is in a liter (L) of a solution. So, to calculate ppm concentration we will divide the milligrams of lead (II) nitride between the liters of paint:
[tex]\begin{gathered} \text{ppm = }\frac{\text{33.1g of lead}\times\frac{1000mg}{1g}}{3L} \\ \text{ppm =11033ppm of lead} \end{gathered}[/tex]The ppm of lead in the paint is 11033ppm.
If I begin with 13.5G of aluminum. How much will I need? I picked B but I’m not sure if I’m correct
Explanation:
Aluminum will react with chlorine gas according to the following reaction:
2 Al (s) + 3 Cl₂ (g) ----> 2 AlCl₃
We have to find the mass of Cl₂ that will completely react with 13.5 g of Al. First we have to convert the mass of Al to moles using its molar mass.
molar mass of Al = 26.98 g/mol
moles of Al = 13.5 g * 1 mol/(26.98 g)
moles of Al = 0.500 mol
2 Al (s) + 3 Cl₂ (g) ----> 2 AlCl₃
Now, according to the coefficients of the reaction, 2 moles of Al will react with 3 moles of Cl₂. So the molar ratio between them is 2 to 3. We can use that relationship to find the number of Cl₂ that will react with 0.500 mol of Al.
2 mol of Al : 3 moles of Cl₂ molar ratio
moles of Cl₂ = 0.500 mol of Al * 3 moles of Cl₂/(2 moles of Al)
moles of Cl₂ = 0.750 mol
And finally we can convert back to grams using the molar mass of Cl₂.
molar mass of Cl₂ = 70.91 g/mol
mass of Cl₂ = 0.750 moles * 70.91 g/(1 mol)
mass of Cl₂ = 53.2 g
Answer: a. 53.2 g of Cl₂ for complete reaction.
Define electronegativity.
A neutral atom has high electronegativity. Describe what happens to this atom during ionic bond formation.
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a) Electronegativity has to do with the fact that electrons are unequally shared in a bond
b) The electronegative tom would receive electrons in an ionic bond.
What is electronegativity?The term electronegativity has to do with the fact that in some atoms, the electron cloud could be closer to them in a covalent bonding situation than to the other atom. You need to recall that in a covalent bond, the electron pair of the bond is shared and the electron cloud is expected to be equidistant between the nuclei of the two atoms that are bonding.
In a case where the electron cloud seems to be closer to one atom than the other then the other atom is said to be highly electronegative. We also need to knw that in an ionic bond, there is a transfer of electrons from one atom to the other.
If one of the bonding atoms in an ionic bond is highly electronegative, it then follows that electrons would be transferred to that atom in the process of ionic bonding.
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How many Chiral centers are in coibacin B
It is to be noted that Coibacin B has three Chiral Centers. A chiral center is a molecule atom that is bound to four separate chemical species, permitting optical isomerism.
What is Coibacin B?Coibacin B is a natural substance with a substantial anti-inflammatory effect and possible utility in the treatment of leishmaniasis, a parasitic illness.
It should be noted that Leishmaniasis is a parasite infection that may be found in the tropics, subtropics, and southern Europe. It is considered a neglected tropical illness (NTD).
Infection with Leishmania parasites, which are disseminated by the bite of phlebotomine sand flies, causes leishmaniasis.
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which atoms has the greatest nuclear charge 7 14N, 6 12C,1 2H or 1 2He
Based on the atomic number of the given elements, the atoms that have the greatest nuclear charge is ¹⁴₇N; option A.
What is the nuclear charge in atoms?The nuclear charge in atoms is the charge in the nucleus due to the presence of the positively-charged protons present in the nucleus of an atom.
The nuclear charge of atoms increases with an increase in the atomic number of the elements.
Hence, for elements in the period table, the size of the nuclear charge increases both down the group and across a period from left to right.
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Katarina is a forensic scientist who finds a stain at a crime scene. What is the first thing she should do?
A.
Build a small frame around the area.
B.
Scrape the substance into a plastic bag.
C.
Make a sketch of the stain in a notepad.
D.
Determine if the substance is blood.
When Katarina finds a stain at a crime scene the first thing she should do is to scrape the substance into a plastic bag. That is option B.
Who is a forensic scientist?A forensic scientist is a professionally trained individual that applies their knowledge in the field of criminology by using evidence found on the crime scene to narrow down a suspect.
When a stain is being noticed by the forensic scientist, the first step should be to secure the stain for further investigation.
To secure the stain, the scientist should scrap the stain into a plastic bag and this should be taken to the laboratory for further evaluation and investigation.
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What consists of water molecules that have escaped or evaporated from the body of water
Water molecules that have escaped or evaporated from the body of water then water get excited and they begin to gain kinetic energy
A water molecule has a three atom two hydrogen and one oxygen atom and that's why water is sometime refred to as H₂O and a single drop of water contain billion drop of molecule and evaporation is the process in which given to the change that occurs to a substance that changes it from its liquid state to a gaseous state
When water get evaporates the molecule of water in a glass will get excited and they begin to gain kinetic energy and vigorously hit the wall of glass
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What is the new volume in liters if 3500 mL of gas is cooled from 80 °C to 25 °C and pressure remains constant? I know the answer is 2.95 L. Please show your work.
Answer:
2.95 L
Explanation:
To find the new volume, you need to use the Charles' Law equation:
V₁ / T₁ = V₂ / T₂
In this equation, "V₁" and "T₁" represent the initial volume and temperature. "V₂" and "T₂" represent the final volume and temperature. Since you want your final volume in liters, you first need to convert 3,500 mL to L. Then, you need to convert the temperatures from Celsius to Kelvin. Finally, you can plug the given values into the equation and simplify to find "V₂".
V₁ = 3,500 mL / 1,000 = 3.5 L V₂ = ? L
T₁ = 80°C + 273 = 353 K T₂ = 25°C + 273 = 298 K
V₁ / T₁ = V₂ / T₂ <----- Charles' Law equation
(3.5 L) / (353 K) = V₂ / (25°C) <----- Insert values
0.00992 = V₂ / (298 K) <----- Divide left side
2.95 = V₂ <----- Multiply both sides by 298 K
3. A 5.00 mole sample of oxygen gas has a pressure of 1.25 atm at 22℃. What is the volume of the gas?
The volume of a gas that has a pressure of 1.25 atm at 22℃ is 96.88L.
How to calculate volume?The volume of a gas can be calculated by using the following formula:
PV = nRT
Where;
P = pressure of the gas V = volume of the gasn = number of moles of the gasT = temperatureR = gas law constantAccording to this question, 5.00 mole sample of oxygen gas has a pressure of 1.25 atm at 22℃. The volume can be calculated as follows:
1.25 × V = 5 × 0.0821 × 295
1.25V = 121.0975
V = 96.88L
Therefore, 96.88L is the volume of the gas
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In an experiment 25 grams of chloroform and 25 grams of chlorine were mixed. Which is the limiting reagent? I picked C but I’m not sure if I’m correct
In this question, we have to find the limiting reactant based on the following reaction:
CHCl3 + Cl2 -> CCl4 + HCl
We have:
25 grams of CHCl3
25 grams of Cl2
The molar ratio between these two compounds is 1:1, 1 mol of CHCl3 for 1 mol of Cl2
Now we have to find the number of moles of each reactant, let's start with CHCl3, we will use its molar mass, 119.38g/mol:
119.38g = 1 mol
25g = x moles
119.38x = 25
x = 25/119.38
x = 0.209 moles of CHCl3
According to the molar ratio, if we have 0.209 moles of CHCl3, we will also have 0.209 moles of Cl2, which has a molar mass of 70.9g/mol
Let's find the mass of 0.209 moles of Cl2:
70.9g = 1 mol
x grams = 0.209 moles of Cl2
x = 14.81 grams
We only need 14.81 grams of Cl2 to react with 25 grams of CHCl3, since we have more Cl2 than we actually need, this makes Cl2 the excess reactant, and CHCl3 will be the limiting reactant. Letter C
Draw electron dot structures for the following substances: a. C12, b. CO, c. CO2 d. NH3, e. CC14, f. H2O
When drawing an electron dot diagram, you need to check the exact number of electrons that an atom has in its shell, only the valence electrons must be drawn
Of the following EM waves, which has the highest frequency?A.X-raysB.Ultraviolet lightC.MicrowavesD.Infrared light
Answer
A. X-rays
Explanation
There are seven regions in the electromagnetic spectrum (EM) which in order of lowest to highest frequency are:
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
Therefore, of the following EM waves given in the options, the one that has the highest frequency is A. X-rays
If the mercury in a barometer raises 22.8 centimeters due to a change in ambient pressure, what is the corresponding change in pressure in atm?
If the mercury in a barometer raises 22.8 centimeters due to a change in ambient pressure, then the corresponding change in pressure would be 0.3 atm.
What is pressure?The total applied force per unit of area is known as the pressure.
The pressure depends both on externally applied force as well the area on which it is applied
As given in the problem If the mercury in a barometer raises 22.8 centimeters due to a change in ambient pressure, then we have to find out the corresponding change in pressure in atm,
760 mm of Hg = 1 atm
76 cm of Hg = 1 atm
1 cm of Hg = 1 / 76 atm
22.8 cm of Hg = 22.8 / 76 atm
= 0.3 atm
Thus , the corresponding change in pressure in atm would be 0.3 atm .
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How much water needs to be added to 65 mL of 3.0 M stock solution to produce a 1.0 M diluted solution?
To answer this question, we have to use the dilution rule, that is represented by the following equation:
[tex]C1V1=C2V2[/tex]Where C1 and C2 are the initial and final concentrations and V1 and V2 are the initial and final volumes.
Solve the equation for V2 to find the final volume:
[tex]\begin{gathered} V2=\frac{C1V1}{C2} \\ V2=\frac{3.0M\cdot65mL}{1.0M} \\ V2=195mL \end{gathered}[/tex]The final volume of the solutions has to be 195mL. Since we already have 65mL, we need to add 130mL of water to have 195mL in total.
It means that the correct answer is 130mL.
I need help regarding the theoretical yield. Why are we doing 6 / 3 in the second step? (20 POINTS)
In calculating the theoretical yield of ammonia, the 6/3 done in the second step is to convert moles of hydrogen to moles of ammonia since the mole ratio of hydrogen to ammonia is 3 : 2.
What is the theoretical yield of a reaction?The theoretical yield of a reaction is the maximum amount of product that can be obtained from a given reaction based on the equation of the reaction.
The theoretical yield of a reaction is obtained from the mole ratio of the limiting reagent and the product of the reaction.
Considering the given reaction whose reaction equation is given below:
N₂ (g) + 3 H₂ (g) ---> 2 NH₃ (g)
Hydrogen is given as the limiting reagent:
The amount of hydrogen present 12 g
Moles of hydrogen = 12 g/ 2 g/mol = 6 moles
Mole ratio of ammonia to hydrogen = 3 : 2
Moles of ammonia produced = moles of hydrogen * mole ratio of ammoia to hydrogen
Moles of ammonia = 6 moles * 2/3 moles = 4 moles
Mass of ammonia produced = 4 moles * 17 g/mol
Mass of ammonia produced = 68 g
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how do you determine what the product of a chemical reaction would be
Answer and explanation
To predict the product, you need to first have or know your reactans, for example, if you have magnesium (Mg) + oxygen (O2), the product should include both reactants. Oxidation numbers also play a role of the final charge of the product, magnesium has a charge of 2+ and O has a charge of 2-, therefore the product will be MgO
Example 2
Na2CO3 + HCl
When sodium carbonate (Na2CO3) reacts with HCl, Na+, O^-2 and CO2 dissociates in the solution, H+ and Cl- also dissociates, what happens is that the oppositely charges ions attract and form compounds, Na is positive and Cl is negative, they will combine to form NaCl, the hydrogen has a positive charge (+1), it will combine with excess oxygen (O^-2) forming water (H2O) and the CO2 will not combine with anything since it is not an ion
Final equation:
Na2CO3 + HCl = NaCl + H2O + CO2
Now we can balance the equation:
Na2CO3 + 2HCl = 2NaCl + H2O + CO2