Answer:
30
Explanation:
CO2 means that there is 1 carbon and 2 oxygens in each CO2 molecule.
If there are 10 atoms of Carbon that requires 20 atoms of oxygen.
The number of atoms present is 10 + 20 = 30 atoms of any kind present. You just need to add.
2- . the number of waves in n *10 bohr's orbit are
Wet helium gas is placed into a balloon at 24.4 degrees Celsius and a pressure of 765.3 mm Hg. What volume (in L) does the dry gas occupy if the water vapor pressure is 24.3 torr and the mass of dried helium gas in the balloon is 0.498 g
Answer:
Hence the Volume of Gas = 3.04 L.
Explanation:
pressure of dry gas = 765.3 - 24.3 = 741 mmhg
Temperature of gas = 24.4+273.15 = 297.55 k
No of mol of gas = 0.498/4 = 0.1245 mol
R = gas constant = 0.0821 l.atm.k-1.mol-1
From ideal-gas equation
PV = nRT
(741/760) x v = 0.1245 x 0.0821 x 297.55
V = Volume of Gas = 3.04 L
Which of these is an organic compound?
CaO
H2SO4
C3H8
H2O2
Answer:
which class are you please mention
LION
If 3.0L of helium at 20°C is allowed to expand to 4.4L, with pressure remain the same
Answer:
This question is asking to find the new temperature
The answer for the final temperature is 429.73K
Explanation:
Using Charles law equation as follows:
V1/T1 = V2/T2
Where;
V1 = initial volume (L)
V2 = final volume (L)
T1 = initial temperature (K)
T2 = final temperature (K)
According to this question;
V1 = 3.0L
V2 = 4.4L
T1 = 20°C = 20 +273 = 293K
T2 = ?
Using V1/T1 = V2/T2
3/293 = 4.4/T2
Cross multiply
293 × 4.4 = 3 × T2
1289.2 = 3T2
T2 = 1289.2 ÷ 3
T2 = 429.73K
15. In the image given below, magnesium metal is coiled as a thin ribbon. What property of metal is exhibited by it? A Ductility B Lustrous C Sonorous D Malleability
Answer: The property of magnesium that is exhibited by it is DUCTILITY. The correct option is A.
Explanation:
Magnesium is a member of the alkaline earth metals. It occurs in nature, only in the combined state, as Epsom salt, dolomite and in many trioxosilicates( IV) including talc and asbestos. They have the following physical properties:
--> Appearance: they are silvery-white solids
--> Relative density: It has a relative density of 1.74
--> DUCTILITY: it's very ductile in nature
--> melting point: it has a melting point of 660°C.
--> Conductivity: They are good conductor of heat and electricity.
Furthermore, DUCTILITY is the physical property of a metal associated with the ability to be hammered thin or stretched into wire without breaking. A metal such as magnesium can therefore be coiled as a thin ribbon without fracturing due to its ductile physical properties.
Match each land resource to its use.
clay - used to make steel
iron ore - used to make batteries
salt - used to make pottery and tiles
aggregate - used in construction
graphite - used as a flavoring in food
i will give 10 points and brainliest!!!
Answer:
Explanation:
We are to match each land resource to what they are being used for.
Clay →→→ used to make pottery and tiles
iron ore →→→ used to make steel
Salt →→→ used as a flavoring in food
aggregate →→→ used in construction
graphite →→→ used to make batteries
Clay is a kind of soil particle that forms as a result of weathering processes. Examples include; pottery clays, glacial clays, and deep-sea clays e.t.c. The presence of one or more clay minerals, as well as variable quantities of organic and detrital components, characterizes all of them. Clay is usually sticky and moist when wet, but hard when dry. They are used in the making of tiles and potteries.
Iron ore: The iron ore deposits are found in the Earth's crust's sedimentary rocks. They're made up of iron and oxygen that mix during the chemical process in marine and freshwater. iron ores are used to produce almost every iron and steel product that we use today.
Aggregate: are utilized in construction activities. It is a material used to mix cement, gypsum, bitumen, or lime to produce concrete in the construction industry.
Graphite: Graphite is a mineral that occurs in both igneous and metamorphic rocks. It is generally generated on the earth's surface when carbon is exposed to high temperatures and pressures. It is mainly used in the production of batteries and electrodes,
convert 14.72 kg to ____ mg
Answer:
14720000
Explanation:
1 kg = 1000000 mg
14.72 kg = 14.72 x 1000000
=14720000
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In the Bohr model of the hydrogen atom, the electron occupies distinct energy states.
a. True
b. False
Answer:
a. True
Explanation:
The Bohr model shows the n-2 as the first transitions between the energy states and hydrogen atom which is shown by changes in the electron structure n = 1 1. In this transition period, the electron moves from the n level to the next level, and energy d transmitted.Carbon NMR spectroscopy produces a spectrum of only carbon-13 nuclei in a sample. The number of carbon signals in the spectrum corresponds to the number of ________in the molecule. In most carbon NMR spectra, the carbon signals appear as singlet peaks .
Answer:
carbons that are in different environments
Explanation:
When molecules are asymmetric every carbon will have its own peak since they are all different and will show up with a different ppm shift. If the molecule has symmetry the carbons that are symmetrical (in the same environment) will have the same ppm shift and will therefore show up as one peak.
An example of a molecule with symmetry is isopropanol which has 3 carbons but only two carbon peaks since the two methyl groups are symmetrical.
An example of a molecule with no symmetry is 3-Nitroaniline where the groups coming off of the benzene ring makes each of the 6 carbons be in different environments and there for all 6 carbons will have different ppm shifts. The result is a carbon NMR that has 6 peaks.
I hope this helps. Let me know if anything is unclear.
Carbon NMR spectroscopy produces a spectrum of only carbon-13 nuclei in a sample. The number of carbon signals in the spectrum corresponds to the number of different number of carbon in the molecule.
What is spectroscopy ?The study of spectroscopy involves measuring and analyzing the electromagnetic spectra that emerge from the interaction of electromagnetic radiation with matter as a function of the radiation's wavelength or frequency.
Three indications Pentane has a mirror plane that runs directly through the center, just like in the ethane example. Three different sorts of carbon atoms may be seen in the molecule of pentane if we rotate it 180 degrees at a time.
Thus, The number of carbon signals in the spectrum corresponds to the number of different number of carbon in the molecule.
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Good evening everyone Write any three difference between symbol and molecular formula answer it ASAP thank u
Answer:
A molecular formula consists of the chemical symbols for the constituent elements followed by numeric subscripts describing the number of atoms of each element present in the molecule.
How many milliliters of 0.204 Mol KMnO4 are needed to react with 3.24 g of iron(II) sulfate, FeSO4? The reation is as folows. 10FeSO4(aq) + 2 KMnO4(aq) = 5Fe2(SO4)3(aq) + 2MnSO4(aq) + K2SO4(aq) + 8H2O(l)
Answer:
Explanation:
nFeSo4=3.36/152
nkmno4=1/5nFeSO4
V=17.68 ml
cesium-131 has a half life of 9.7 days. what percent of a cesium-131 sample remains after 60 days?
Explanation:
From the question given above, the following data were obtained:
Half-life (t½) = 9.7 days
Time (t) = 60 days
Percentage remaining after 60 days =?Next, we shall determine the number of half-lives that has elapsed. This can be obtained as follow:
Half-life (t½) = 9.7 days
Time (t) = 60 days
Number of half-lives (n) =?
n = t / t½
n = 60 / 9.7Finally, we shall determine the percentage remaining. This can be obtained as follow:
Let the original amount be N₀
Let the amount remaining be N
Number of half-lives (n) = 60 / 9.7
N = N₀ / 2ⁿ
Divide both side by N₀
N/N₀ = 1/2ⁿ
N/N₀ = 1 / 2⁽⁶⁰÷⁹•⁷⁾
N/N₀ = 0.0137
Multiply by 100 to express in percentage
N/N₀ = 0.0137 × 100
N/N₀ = 1.37%Therefore, the percentage remaining after 60 days is 1.37%
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A Grignard reagent is prepared by reacting trans-1-bromo-1-butene with magnesium. What are the products of the reaction when this reagent is reacted with: a. Ethanol
Solution :
A Grignard compound or a Grignard reagent is defined as a chemical compound having a generic formula of R−Mg−X.
Here, X = halogen
R = organic group
The Grignard reagents are obtained by treating the organic halide with a magnesium metal.
In the context, when trans-1-bromo-1-butene is reacted with magnesium, a Grignard reagent is produced.
When this Grignard reagent is reacted with an ethanol, the following product is obtained in the attachment :
The critical mass of fissionable material is the largest mass necessary to sustain a nuclear fission chain reaction. single mass value that can sustain a nuclear fission chain reaction. mass at the critical point, which can sustain a nuclear fission chain reaction. smallest mass necessary to sustain a nuclear fission chain reaction.
Answer:
smallest mass necessary to
Explanation:
The critical mass for a fissionable material is the smallest and the lowest quantity of a particular fissile material required to generate a self-sustaining fission chain reaction under specified conditions. The size's features are determined by a number of variables. Examples include;
The type of fissile material employed, its purity as well as concentration, the shape of the surrounding reaction system e.t.c.
Answer:
Fill in the blanks with the terms that complete the sentences about nuclear power plants.
Without a critical mass of fissionable material, a nuclear reaction cannot be sustained. The turbine is powered by steam.
Explanation:
The answers to both parts are marked in bold. I just answered these questions on Edge and they were both correct. Hope this helps. Please mark my answers as the brainiest. THANK YOU!!!!!!!!!!!!!!!!!!!
Given the following reaction: 3CuCl2(aq) 2Na3PO4(aq) --> Cu3(PO4)2(s) 6NaCl(aq) MM (g/mol) 134.45 163.94 380.58 58.44 If 285 mL of 6.3 M CuCl2 is added to excess Na3PO4 solution, how much precipitate( in grams) is produced Note: Write answer to two decimal places.
Answer:
227.78g of the precipitate are produced
Explanation:
Based on the reaction, 3 moles of CuCl2 produce 1 mole of Cu3(PO4)2 (The precipitate).
To solve this question we need to find the moles of CuCl2 added. With these moles and the reactio we can find the moles of Cu3(PO4)2 and its mass as follows:
Moles CuCl2:
285mL = 0.285L * (6.3mol / L) = 1.7955 moles CuCl2
Moles Cu3(PO4)2:
1.7955 moles CuCl2 * (1mol Cu3(PO4)2 / 3mol CuCl2) = 0.5985 moles Cu3(PO4)2
Mass Cu3(PO4)2 -380.58g/mol-
0.5985 moles Cu3(PO4)2 * (380.58g/mol) =
227.78g of the precipitate are produced
Arrange the following in order of increasing melting point: NaCl, H2O, CH4, C6H4(OH)2.
a. NaCl < H2O < CH4 < C6H4(OH)2
b. CH4 < H2O < NaCl < C6H4(OH)2
c. CH4 < H2O < C6H4(OH)2 < NaCl
d. CH4 < C6H4(OH)2 < H2O < NaCl
e. CH4 < NaCl < C6H4(OH)2 < H2O
Explanation:
one thing to know is that higher surface area = higher boiling point.
NaCl has the smallest surface area, so it's the first one.
H2O has less surface area than methane, so it's second.
Methane has more surface area than H20, so it's third.
The big molecule has the most surface area, so it's last
Temperature measures the average kinetic energy of particles of the substances. Melting point is directly proportional to surface area. Therefore, the correct option is option C.
What is temperature?Temperature is used to measure degree or intensity of heat of a particular substance. Temperature is measured by an instrument called thermometer.
Temperature can be measured in degree Celsius °c, Kelvin k or in Fahrenheit. Temperature is a physical quantity. Heat always flow from higher temperature source to lower temperature source.
We can convert these units of temperature into one another. The relationship between degree Celsius and Fahrenheit can be expressed as:
°C={5(°F-32)}÷9
Melting point is directly proportional to surface area. NaCl has the smallest surface area. Water has less surface area than methane. Methane has more surface area than H[tex]_2[/tex]O.
Therefore, the correct option is option C.
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A saturated solution of potassium iodide contains, in each 100 mL, 100 g of potassium iodide. The solubility of potassium iodide is 1 g in 0.7 mL of water. Calculate the specific gravity of the saturated solution
Answer:
Specific gravity of the saturated solution is 2
Explanation:
The specific gravity is defined as the ratio between density of a solution (In this case, saturated solution of potassium iodide, KI) and the density of water. Assuming density of water is 1:
Specific gravity = Density
The density is the ratio between the mass of the solution and its volume.
In 100mL of water, the mass of KI that can be dissolved is:
100mL * (1g KI / 0.7mL) = 143g of KI
That means all the 100g of KI are dissolved (Mass solute)
As the volume of water is 100mL, the mass is 100g (Mass solvent)
The mass of the solution is 100g + 100g = 200g
In a volume of 100mL, the density of the solution is:
200g / 100mL = 2g/mL.
The specific gravity has no units, that means specific gravity of the saturated solution is 2
Consider the following chemical reaction:
2SO2 (g) + O2 (g) -----------> 2SO3 (g)
1.50 L. of sulfur trioxide at the pressure of 1.20 atm. and temperature of 25 oC is mixed with excess of oxygen.
Calclate volume of the product in L. at STP.
A. 11.2 L.
B. 1.65 L.
C. 16.5 L.
D. 0.129 L.
Answer:
B. 1.65 L
Explanation:
Step 1: Write the balanced equation
2 SO₂(g) + O₂(g) ⇒ 2 SO₃(g)
Step 2: Calculate the moles of SO₂
The pressure of the gas is 1.20 atm and the temperature 25 °C (298 K). We can calculate the moles using the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 1.20 atm × 1.50 L / (0.0821 atm.L/mol.K) × 298 K = 0.0736 mol
Step 3: Calculate the moles of SO₃ produced
0.0736 mol SO₂ × 2 mol SO₃/2 mol SO₂ = 0.0736 mol SO₃
Step 4: Calculate the volume occupied by 0.0736 moles of SO₃ at STP
At STP, 1 mole of an ideal gas occupies 22.4 L.
0.0736 mol × 22.4 L/1 mol = 1.65 L
Which of the following statements is/are correct? 1. There are 5 orbitals in
the d subshell. 2. The d orbitals can accommodate 14 electrons. 3. The first
shell contains s and p orbitals. 4. The s orbital can accommodate 2 electrons.
A. 1 and 4
B. 2 and 3
C. 3 and 4
D. 2 and 4
describe briefly the laboratory preparation of methane gas
Answer:
In the laboratory, methane is formed by heating sodium ethanoate with a mixture of sodium hydroxide and calcium oxide, called soda lime, on heating in the presence of a catalyst, calcium oxide, the -COONa group from sodium ethanoate is replaced by the hydrogen atom from sodium hydroxide, forming methane and sodium
Explanation:
Balance the following equations and write the corresponding ionic and net ionic equations (if appropriate):
a. CH3COOH(aq) + KOH(aq) →
b. H2CO3(aq) + NaOH(aq) →
c. HNO3(aq) + Ba(OH)2(aq) →
Explanation:
here are your dissolutions
To calculate the atoms of an element in a given molecule, we need to multiply stoichiometry by the number that is written on the foot of that element. Therefore, the balanced equation are
CH[tex]_3[/tex]COOH + KOH [tex]\rightarrow[/tex]CH[tex]_3[/tex]COOK + H[tex]_2[/tex]O
H[tex]_2[/tex]CO[tex]_3[/tex] (aq) + 2 NaOH(aq) [tex]\rightarrow[/tex]Na[tex]_2[/tex]CO[tex]_3[/tex](aq) + 2 H[tex]_2[/tex]O
HNO[tex]_3[/tex] + Ba(OH)[tex]_2[/tex][tex]\rightarrow[/tex]Ba(NO[tex]_3[/tex])[tex]_2[/tex]+ H[tex]_2[/tex]O
What is Balanced equation?Balanced equation is the one in which the total number of atoms of a species on reactant side is equal to the total number of atoms on product side. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, displacement reaction.
The other characteristic of balanced reaction is that physical state should be written with each compound or molecule on reactant and product side. Physical state should be written in brackets. s means solid, l means liquid, g means gas.
The balanced equation can be written as
CH[tex]_3[/tex]COOH + KOH [tex]\rightarrow[/tex]CH[tex]_3[/tex]COOK + H[tex]_2[/tex]O
H[tex]_2[/tex]CO[tex]_3[/tex] (aq) + 2 NaOH(aq) [tex]\rightarrow[/tex]Na[tex]_2[/tex]CO[tex]_3[/tex](aq) + 2 H[tex]_2[/tex]O
HNO[tex]_3[/tex] + Ba(OH)[tex]_2[/tex][tex]\rightarrow[/tex]Ba(NO[tex]_3[/tex])[tex]_2[/tex]+ H[tex]_2[/tex]O
Therefore, the balanced equation are
CH[tex]_3[/tex]COOH + KOH [tex]\rightarrow[/tex]CH[tex]_3[/tex]COOK + H[tex]_2[/tex]O
H[tex]_2[/tex]CO[tex]_3[/tex] (aq) + 2 NaOH(aq) [tex]\rightarrow[/tex]Na[tex]_2[/tex]CO[tex]_3[/tex](aq) + 2 H[tex]_2[/tex]O
HNO[tex]_3[/tex] + Ba(OH)[tex]_2[/tex][tex]\rightarrow[/tex]Ba(NO[tex]_3[/tex])[tex]_2[/tex]+ H[tex]_2[/tex]O
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34. 3.15 mol of an unknown solid is placed into enough water to make 150.0 mL of solution. The solution's temperature increases by 11.21°C. Calculate ∆H, in kJ/mol, for the dissolution of the unknown solid. (The specific heat of the solution is 4.184 J/g･°C and the density of the solution is 1.20 g/mL).
Answer:
ΔH = 2.68kJ/mol
Explanation:
The ΔH of dissolution of a reaction is defined as the heat produced per mole of reaction. We have 3.15 moles of the solid, to find the heat produced we need to use the equation:
q = m*S*ΔT
Where q is heat of reaction in J,
m is the mass of the solution in g,
S is specific heat of the solution = 4.184J/g°C
ΔT is change in temperature = 11.21°C
The mass of the solution is obtained from the volume and the density as follows:
150.0mL * (1.20g/mL) = 180.0g
Replacing:
q = 180.0g*4.184J/g°C*11.21°C
q = 8442J
q = 8.44kJ when 3.15 moles of the solid react.
The ΔH of the reaction is:
8.44kJ/3.15 mol
= 2.68kJ/mol
Question 14
2 pts
A chemist wants to make 100 mL of a 0.500 M solution of NaCl. They have a
stock solution of 1.2 M NaCl. How much of the original stock solution do they
need to make their new dilute solution?
Explanation:
From the question given above, the following data were obtained:
Molarity of stock solution (M₁) = 1.2 M
Molarity of diluted solution (M₂) = 0.5 M
Volume of diluted solution (V₂) = 100 mL
Volume of stock solution needed (V₁) =?The volume of stock solution needed can be obtained by using the dilution formula as illustrated below:
M₁V₁ = M₂V₂1.2 × V₁ = 0.5 × 100
1.2 × V₁ = 50
Divide both side by 1.2
V₁ = 50 / 1.2
V₁ ≈ 42 mLThus, 42 mL of the stock solution is needed.
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Answer:
They need 41.7 mL of the original stock solution.
Explanation:
We can use the following equation for dilutions:
Cc x Vc = Cd x Vd
Where Cc and Vc are the concentration and volume values in the concentrated condition, whereas Cd and Vd are the concentration and volume values in the diluted condition.
The concentrated solution is the original stock solution, and it has:
Cc = 1.2 M
The diluted solution must be:
Cd = 0.500 M
Vd = 100 mL
So, we have to calculate Vc. For this, we replace the data in the equation:
[tex]V_{c} = \frac{C_{d} V_{d} }{C_{c} } = \frac{(0.500 M)(100 mL)}{1.2 M} = 41.7 mL[/tex]
Therefore, 41.7 mL of 1.2 M original stock solution are required to make 100 mL of a diluted solution with a concentration of 0.500 M.
Tech A says that hydrocarbons are a result of complete combustion. Tech B says that a catalytic converter creates a chemical reaction, changing carbon monoxide and hydrocarbons to water and carbon dioxide. Who is correct
Answer:
Neither Tech A nor B is correct
Explanation:
Combustion is a chemical reaction that occurs when a chemical molecule(s) interacts quickly with oxygen and produces heat.
When hydrocarbon undergoes a complete combustion reaction, they produce water and CO2.
Tech B is also incorrect because the main purpose of a catalytic converter is to accelerate and speed up the chemical reaction rates, Hence, they are not involved in chemical reaction formation. Catalytic converters are utilized as a control device in exhaust emission to lessen the effect of toxic gas fumes.
Is a 4p S 4s transition allowed in sodium? If so, what is its wavelength? If not, why not? b. Is a 3d S 4s transition allowed in sodium? If so, what is its wavelength? If not, why not? g
Answer:
a) 4p ⇒ 4s transition is Allowed
b) 3d ⇒ 4s transition not allowed
Explanation:
a) 4p ⇒ 4s transition
This transition is allowed because for a 4p state; l = 1 and for a 4s state I = 0
hence Δl = 1 - 0 = 1
Energy of 4p ( Ei ) = 3.75eV
Energy of 4s ( E2 ) = 3.19 eV
where : λ = 1240 eV nm / ( E₂ - E₁ )
= 2214 nm ≈ 2.214 μm
b) 3d ⇒ 4s transition
This transition is not allowed
a 3d state , l = 2 while for 4s state l = 0
hence Δl = 2 - 0 = 2
therefore the transition is not allowed
Please guys please answer this
Answer:
1. Because the rules will keep you safe it prevents you from getting hurt.
2.i) don't taste chemical
ii) Always wear protective gears
iii) be careful with tool
iv) wear protective gloves
Explanation:
help everyone get out quickly
Can steel turn into gas? ( A random question that came to mind. I have no idea if it is or isn't possible.)
Answer:
YES STEEL CAN TURN INTO GAS .
Answer: yes it can!
Explanation:
A new member of your team is visually impaired. He's having a hard time reading his computer screen. How can you show that you value diversity? a) Suggest the organization may not be a great fit. O b) Tell him to apply for a different job within the organization that does not b) require computer usage. 12 Od Tell him that he might want to schedule an eye exam. c) d) Provide access to technology that can magnify or read what is on the computer screen.
Answer:
C
Explanation:
If he can't read his computer screen. Means his eyes have problem
A new member of your team is visually impaired. He's having a hard time reading his computer screen. value diversity require computer usage. 12 Tell him that he might want to schedule an eye exam. Therefore, option C is correct.
What is value diversity ?Institutions and community members who value diversity do so in order to recognize the advantages of both their differences and commonalities. They make a deliberate effort to forge enduring connections between individuals and organizations with a broad membership.
When people's unique qualities, abilities, interests, and viewpoints are recognized and supported, they develop a stronger sense of self and health and achieve better results in their academic and professional endeavors.
Although diversity and inclusion are related ideas, they are not the same thing. Diversity has to do with representation or how something is put together. The degree to which the contributions, presence, and viewpoints of other groups of individuals are appreciated and incorporated into a setting is referred to as inclusion.
Thus, option C is correct.
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Methyl pentanoate condensed structural formula
Answer:
C6H12O2 is the formula for Methyl pentanoate
Write chemical equations and corresponding equilibrium expressions for each of the two ionization steps of carbonic acid. Part A Write chemical equations for first ionization step of carbonic acid. Express your answer as a chemical equation. Identify all of the phases in your answer.
Solution :
[tex]H_2CO_3[/tex] is considered a diprotic acid.
Sp it can dissociate in solution by giving two protons.
Chemical equations for the first step of carbonic acid is :
First ionization
[tex]$H_2CO_3(aq) + H_0(1) \rightleftharpoons H_.O^+(aq) + HCO_3^-(aq)$[/tex]
Equilibrium constant expression is
[tex]$K_{a}_{1}=\frac{[H_3O^+][HCO_3^-]}{[H_2CO_3]}$[/tex]
Second ionization -
[tex]$HCO_3^-(aq) + H_2O(l) \rightleftharpoons H_3O^+(aq) + CO_3^{2-}(aq)$[/tex]
Equilibrium constant expression is
[tex]$K_{a2}=\frac{[H_3O^+][CO_3^{2-}]}{[HCO_3^-]}$[/tex]
