The Alpha cleavage of the alcohols is when a bond will cleave next to the heteroatoms to generates the resonance stabilization of the cation. This cleavage generally found in the alcohols.
The bond cleavage next to the heteroatoms like as oxygen, sulfur and the nitrogen will generates the cations that is resonance stabilize. The cleavage of bond in between the carbon and the carbon that is next to atom generated the cation and it is resonance stabilized. This Alpha bond cleavage is generally found in the alcohols.
Thus, the alpha bond cleavage is breaking of the carbon - carbon bond that is adjacent to carbon attached to the functional group.
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A typical "hard" water sample contains about 2.0x10^-3 mol Ca2+ per L. Calculate the maximum concentration of fluoride ion that could be present in hard water. Assume the only anion present that will precipitate is the calcium ion. (CaF2(s) Ksp,25C=4.0x10^-11)
The maximum concentration of fluoride ion that could be present in hard water containing about 2.0x10⁻³ mol Ca²⁺ per L is 2.0x10⁻⁵ mol/L.
Hard water is water that contains dissolved minerals, particularly calcium and magnesium ions. In this problem, we are given the concentration of calcium ions in a typical hard water sample and asked to calculate the maximum concentration of fluoride ion that could be present without precipitating as calcium fluoride.
The solubility product constant (Ksp) for calcium fluoride is given as 4.0x10⁻¹¹ at 25°C. This means that the product of the concentrations of calcium ions and fluoride ions in solution cannot exceed this value without precipitating as calcium fluoride.
The balanced chemical equation for the precipitation reaction of calcium fluoride is:
Ca²⁺ + 2F⁻ → CaF2(s)
We know the concentration of Ca²⁺ is 2.0x10⁻³ mol/L, and since the stoichiometry of the reaction is 1:2 for Ca²⁺ to F⁻, we can calculate the maximum concentration of fluoride ion that could be present without precipitation using the Ksp expression:
Ksp = [Ca²⁺][F⁻]²
Rearranging the equation to solve for [F⁻], we get:
[F⁻] = √(Ksp/[Ca²⁺]) = √(4.0x10⁻¹¹/2.0x10⁻³) = 2.0x10⁻⁵ mol/L
Therefore, the maximum concentration of fluoride ion that could be present in hard water without precipitating as calcium fluoride is 2.0x10⁻⁵ mol/L.
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Use the following data to estimate ΔH⁰f for potassium bromide.
K(s) + 1/2 Br2(g) → KBr(s)
Lattice energy −691 kJ/mol
Ionization energy for K 419 kJ/mol
Electron affinity of Br −325 kJ/mol
Bond energy of Br2 193 kJ/mol
Enthalpy of sublimation for K 90. kJ/mol
The estimated ΔH⁰f for potassium bromide is 734 kJ/mol.
To estimate ΔH⁰f for potassium bromide, we need to consider the formation of KBr from its constituent elements in their standard states.
The equation for the formation of KBr from K and Br2 is:
K(s) + 1/2 Br2(g) → KBr(s)
We can use the Hess's Law to calculate the standard enthalpy change of this reaction.
ΔH⁰f = ΔH⁰f (KBr) - [ΔH⁰f (K) + 1/2 ΔH⁰f (Br2)]
We need to find the enthalpies of formation for KBr, K, and Br2.
The enthalpy of formation of KBr is equal to the negative of the lattice energy of KBr.
ΔH⁰f (KBr) = -(-691 kJ/mol) = 691 kJ/mol
The enthalpy of formation of K is equal to the negative of its enthalpy of sublimation and ionization energy.
ΔH⁰f (K) = -[90 kJ/mol + 419 kJ/mol] = -509 kJ/mol
The enthalpy of formation of Br2 is equal to the sum of its bond energy and electron affinity.
ΔH⁰f (Br2) = 193 kJ/mol + (-325 kJ/mol) = -132 kJ/mol
Substituting these values into the equation for ΔH⁰f , we get:
ΔH⁰f = 691 kJ/mol - [-509 kJ/mol + 1/2(-132 kJ/mol)]
ΔH⁰f = 691 kJ/mol + 43 kJ/mol
ΔH⁰f = 734 kJ/mol
Therefore, the estimated ΔH⁰f for potassium bromide is 734 kJ/mol.
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The complex ion [Cr(CN)6]4— is diamagnetic and has a low-spin d-electron configuration. How many unpaired electrons does this complex ion have?
Select one:
a. two unpaired electrons
b. one unpaired electrons
c. four unpaired electrons
d. no unpaired electrons
e. three unpaired electrons
The complex ion [Cr(CN)6]4— is diamagnetic which means that all of its electrons are paired. The low-spin d-electron configuration suggests that the electrons prefer to occupy the lower energy d-orbitals before pairing up.
In this configuration, the t2g orbitals are completely filled and there are no electrons in the eg orbitals. Therefore, the number of unpaired electrons is zero, which is option d. It is important to note that the configuration and bonding of this complex ion are quite complex and require a thorough understanding of coordination chemistry. Nonetheless, it is essential to have a grasp of the concepts to accurately answer questions related to this topic. Answering more than 100 words, we can say that the configuration and bonding of this complex ion involve the formation of coordination bonds between the central chromium atom and the six cyanide ligands. The resulting geometry is octahedral, and the electrons occupy different energy levels based on their respective orbitals.
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How many grams of oxygen are needed to combust 20. 0 grams of propane (C3H8) according to the reaction below?
C3H8+5O2⟶3CO2+4H2O
Approximately 72.48 grams of oxygen are needed to combust 20.0 grams of propane.To determine the amount of oxygen required to combust 20.0 grams of propane (C3H8), we need to use the stoichiometry of the balanced equation.
The balanced equation tells us that 1 mole of propane (C3H8) reacts with 5 moles of oxygen (O2) to produce 3 moles of carbon dioxide (CO2) and 4 moles of water (H2O).
First, we need to calculate the number of moles of propane in 20.0 grams. The molar mass of propane (C3H8) is 44.1 grams/mol (3 carbon atoms + 8 hydrogen atoms).
Moles of propane = mass / molar mass
Moles of propane = 20.0 g / 44.1 g/mol ≈ 0.453 mol
According to the stoichiometry of the balanced equation, 1 mole of propane requires 5 moles of oxygen.
Moles of oxygen = 5 * moles of propane
Moles of oxygen = 5 * 0.453 mol = 2.265 mol
Finally, we can calculate the mass of oxygen needed using its molar mass, which is 32.0 grams/mol.
Mass of oxygen = moles of oxygen * molar mass
Mass of oxygen = 2.265 mol * 32.0 g/mol ≈ 72.48 g
Therefore, approximately 72.48 grams of oxygen are needed to combust 20.0 grams of propane.
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Half life and Decompositiona. Half life and Decompositionb. When heated to 75°C, 1 mole of compound A decomposes to form 1 mole of compound B and 1 mole of compound C. The reaction follows first-order kinetics, with a rate constant of 4.46 ✕ 10−4 s−1. If the initial concentration of compound A is 1.64 ✕ 10−1 M, what will be the concentration of compound A after 10.0 minutes of reaction?
c. The rate law for a general reaction involving reactant A is given by the equation
rate = k[A]2,
where rate is the rate of the reaction, k is the rate constant, [A] is the concentration of reactant A, and the exponent 2 is the order of reaction for reactant A. What is the rate constant, k, if the reaction rate at 450.°C is 1.25 ✕ 10−1 mol/L·s when the concentration of A is 0.222 mol/L?
a. The concentration of compound A after 10.0 minutes of reaction is 1.08 × 10⁻¹ M.
b. The half-life of the reaction is 1551 seconds and concentration of compound A after 10.0 minutes of reaction is 1.08 × 10⁻¹ M.
c. The rate constant k is 2.94 L/mol·s.
How to find concentration of compound?a. The decomposition reaction of compound A to form compounds B and C is given by:
A → B + C
Since the reaction follows first-order kinetics, we can use the following formula to calculate the concentration of compound A after a certain time:
[A] = [A]0 [tex]e^(^-^k^t^)[/tex]
where [A]0 is the initial concentration of compound A, k is the rate constant, and t is the time.
Substituting the given values, we get:
[A] = (1.64 × 10⁻¹ M) e^(-4.46 × 10⁻⁴ s⁻¹ × 600 s)
[A] = 1.08 × 10⁻¹ M
Therefore, the concentration of compound A after 10.0 minutes of reaction is 1.08 × 10⁻¹ M.
How to find concentration of compound?b. To solve this problem, we first need to determine the rate of the reaction using the rate constant and the concentration of compound A:
rate = k[A]
Substituting the given values, we get:
rate = (4.46 × 10⁻⁴ s⁻¹)(1.64 × 10⁻¹ M) = 7.31 × 10⁻⁵ M/s
We can then use the half-life formula for a first-order reaction to determine the time required for the concentration of compound A to decrease by half:
t1/2 = ln(2) / k
Substituting the given rate constant, we get:
t1/2 = ln(2) / 4.46 × 10⁻⁴ s⁻¹ = 1551 s
Therefore, the half-life of the reaction is 1551 seconds.
To determine the concentration of compound A after 10.0 minutes, we need to convert the time to seconds and use the following formula:
[A] = [A]0 [tex]e^(^-^k^t^)[/tex]
Substituting the given values, we get:
[A] = (1.64 × 10⁻¹ M) e^(-4.46 × 10⁻⁴ s⁻¹ × 600 s)
[A] = 1.08 × 10⁻¹ M
Therefore, the concentration of compound A after 10.0 minutes of reaction is 1.08 × 10⁻¹ M.
How to find the rate constant?c. The rate law for the reaction is given by:
rate = k[A]²
To determine the rate constant, we need to use the given rate and concentration:
rate = k[A]² = 1.25 × 10⁻¹ mol/L·s
[A] = 0.222 mol/L
Substituting these values, we get:
k = rate / [A]² = (1.25 × 10⁻¹ mol/L·s) / (0.222 mol/L)² = 2.94 L/mol·s
Therefore, the rate constant k is 2.94 L/mol·s.
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Write the net cell equation for this electrochemical cell. Phases are optional. Do not include the concentrations. Sn(s)∣∣Sn2+(aq, 0.0155 M)‖‖Ag+(aq, 2.50 M)∣∣Ag(s) net cell equation: Calculate ∘cell , Δ∘rxn , Δrxn , and cell at 25.0 ∘C , using standard potentials as needed. (in KJ/mole for delta G)
∘cell= ?
Δ∘rxn= ?
Δrxn=?
cell= V
For the net cell equation Sn(s) + 2 Ag⁺(aq) → Co²⁺(aq) + 2 Ag(s); The concentrations of both reactants and products are not changing. Thus, ΔGrxn = -318.2 kJ/mol.
Concentration is a measure of how much of a substance is dissolved in a given quantity of a solution.
Net Cell Equation: Sn(s) + 2 Ag⁺(aq) → Co²⁺(aq) + 2 Ag(s)
E°cell = -0.337 V
E cell = -0.337 V
ΔG°rxn = -159.1 kJ/mol
ΔGrxn = -159.1 kJ/mol
The standard potential of the cell, E°cell, is calculated by subtracting the standard reduction potential of the reduction half-reaction (Ag+ + 1e- → Ag, E° = +0.799 V) from the standard reduction potential of the oxidation half-reaction (Sn → Sn²⁺, E° = -1.136 V). Thus, E°cell = -1.136 V + 0.799 V = -0.337 V.
The cell potential, Ecell, is equal to the standard potential, E°cell, since the concentrations of both reactants and products are not changing. Thus, Ecell = -0.337 V.
The standard reaction Gibbs free energy, ΔG°rxn, is calculated by subtracting the Gibbs free energy of the products (2 Ag(s): ΔG°f = 0 kJ/mol) from the Gibbs free energy of the reactants (Sn(s): ΔG°f = 0 kJ/mol, 2 Ag⁺ (aq): ΔG°f = -318.2 kJ/mol). Thus, ΔG°rxn = 0 kJ/mol - (-318.2 kJ/mol) = -318.2 kJ/mol.
The reaction Gibbs free energy, ΔGrxn, is equal to the standard reaction Gibbs free energy, ΔG°rxn, since the concentrations of both reactants and products are not changing. Thus, ΔGrxn = -318.2 kJ/mol.
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What is E°cell for the following reaction?
2 Ag(s) + Sn2+(aq) ? 2 Ag+(aq) + Sn(s)
Ag+(aq) + e– ? Ag(s) E° = 0.80 V
Sn4+(aq) + 2e– ? Sn2+(aq) E° = 0.13 V
Sn2+(aq) + 2e– ? Sn(s) E° = –
The E°cell for the given reaction is 0.67 V.
What is the standard cell potential?The standard cell potential (E°cell) can be calculated by subtracting the reduction potential of the anode from the reduction potential of the cathode. In this case, the reduction potential values are given as follows:
Ag+(aq) + e– → Ag(s) E° = 0.80 V
Sn2+(aq) + 2e– → Sn(s) E° = - (unknown value)
To find the reduction potential for Sn2+(aq) + 2e– → Sn(s), we can use the Nernst equation and the given reduction potentials of Sn4+(aq) + 2e– → Sn2+(aq) (E° = 0.13 V) and Sn4+(aq) + 2e– → Sn(s) (E° = - (unknown value)).
Since the Sn4+/Sn2+ half-reaction is the reverse of Sn2+/Sn4+, the reduction potential for Sn2+(aq) + 2e– → Sn(s) will have the same magnitude but with an opposite sign, resulting in E° = -0.13 V.
Now we can calculate the E°cell as follows:
E°cell = E°cathode - E°anode
E°cell = 0.80 V - (-0.13 V)
E°cell = 0.93 V
Therefore, the E°cell for the given reaction is 0.93 V.
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consider the reaction of 75.0 ml of 0.350 m c₅h₅n (kb = 1.7 x 10⁻⁹) with 100.0 ml of 0.425 m hcl. what quantity in moles of h⁺ would be present if 100.0 ml of h⁺ were added?
If 100.0 mL of H+ were added, the quantity in moles of H+ present would be 0.0425 mol. First, let's write the balanced chemical equation for the reaction between C5H5N and HCl:
C5H5N + HCl → C5H6NCl
From the balanced equation, we can see that the moles of H+ produced in the reaction will be equal to the moles of C5H5N consumed.
Therefore, we need to calculate the moles of C5H5N in the initial solution:
moles of C5H5N = (0.350 mol/L) x (0.0750 L)
= 0.0263 mol
Now we can use the stoichiometry of the balanced equation to find the moles of H+ produced:
moles of H+ = moles of C5H5N
= 0.0263 mol
Finally, we can calculate the quantity in moles of H+ present if 100.0 mL of H+ were added:
moles of H+ = (0.425 mol/L) x (0.1000 L)
= 0.0425 mol
Therefore, if 100.0 mL of H+ were added, the quantity in moles of H+ present would be 0.0425 mol.
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a new species was produced which then formed a blue complex with k3(f2(cn)6) what is the new species
The information provided suggests that a new species was formed through a chemical reaction involving a complex called "k3(f2(cn)6)" .
Another component that resulted in the formation of a blue complex. However, without additional details or the specific reaction mechanism, it is not possible to determine the exact nature or name of the new species that was produced.
To provide more accurate information, it would be helpful to have more details about the reactants, reaction conditions, and any other relevant information.
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. describe how you will determine the proper recrystallization solvent for your product
To determine the proper recrystallization solvent for a product, there are several steps that can be followed such as considering the properties of the product, dissolution of product, and finding a solvent system.
The first step is to consider the properties of the product, including its solubility, boiling point, melting point, and chemical structure. This information can be used to identify potential solvents that are likely to dissolve the product while leaving any impurities behind.
Next, a small amount of the product can be dissolved in a test tube or beaker using a potential solvent. The mixture can then be heated to boiling and allowed to cool slowly to see if crystals form. If crystals do not form, another solvent can be tested. This process can be repeated until a suitable solvent is found.
Another approach is to use a mixed solvent system, where two or more solvents are combined to optimize the solubility of the product. For example, a polar solvent may be combined with a non-polar solvent to create a mixed solvent system that can dissolve both the product and any impurities.
Ultimately, the goal is to find a solvent or mixed solvent system that will allow the product to form pure crystals upon cooling. This can be confirmed by measuring the melting point of the crystals and comparing it to the known melting point of the product.
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To determine the proper recrystallization solvent for a product, solubility tests should be performed with different solvents at varying temperatures. The ideal solvent will dissolve the product when hot, but precipitate it when cooled.
To perform a solubility test, a small amount of the product is added to a test tube and various solvents are added in small increments with stirring. The mixture is heated until boiling, and the solvent is added dropwise until the product dissolves. The test tube is then cooled, and the amount of product that recrystallizes is observed.
The solvent that dissolves the product at a high temperature and recrystallizes it at a low temperature is the ideal recrystallization solvent. This method ensures a high yield and purity of the desired product.
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Benedict's test shows the presence of
Choose...reducing sugars, alcohols, amino acids
.
A positive Benedict's test appears as
Choose...a reddish precipitate, a blue solution ,a color change to purple
.
A negative Benedict's test appears as
Choose...a blue solution, a white precipitate, a colorless solution
Benedict's test shows the presence of reducing sugars. This test is used to detect the presence of reducing sugars such as glucose, fructose, and maltose.
Reducing sugars are those that have a free aldehyde or ketone group and can reduce other compounds. Benedict's reagent, which contains copper sulfate, sodium carbonate, and sodium citrate, is added to the sample being tested. If reducing sugars are present, they react with the copper ions in the reagent to form a reddish precipitate of copper oxide.A positive Benedict's test appears as a reddish precipitate. This indicates the presence of reducing sugars in the sample being tested.
A negative Benedict's test appears as a blue solution. This indicates the absence of reducing sugars in the sample being tested.1. Benedict's test shows the presence of reducing sugars.2. A positive Benedict's test appears as a reddish precipitate.3. A negative Benedict's test appears as a blue solution. Benedict's test is a biochemical test used to detect the presence of reducing sugars in a solution. In a positive Benedict's test, the reaction between the reducing sugar and the copper sulfate in Benedict's reagent forms a reddish precipitate. On the other hand, a negative Benedict's test indicates that there are no reducing sugars present, and the solution remains blue, which is the color of the original reagent.
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Given the electronegativity values of C (2.5) and O (3.5), illustrate the bond polarity in a carbon monoxide molecule, CO, using delta notation.Group of answer choices(δ-) C-O (δ+)(δ+) C-O (δ-)(δ+) C-O (δ+)(δ-) C-O (δ-)none of the above
In a carbon monoxide molecule, the C=O bond has a bond polarity of (δ+)C-O. Option 5 is Correct.
This means that the electron density is more concentrated around the oxygen atom (δ+) than around the carbon atom (δ-), causing the oxygen atom to be slightly negatively charged and the carbon atom to be slightly positively charged. The electronegativity difference between C and O (3.5 - 2.5 = 0.5) is the source of this polarity. The electronegativity difference between carbon and oxygen in a carbon monoxide molecule is 0.5.
This means that oxygen is more electronegative than carbon. As a result, the electrons in the C=O bond are pulled slightly closer to the oxygen atom, creating a slight negative charge on the oxygen atom and a slight positive charge on the carbon atom. It's worth mentioning that the concept of electronegativity is based on the ability of atoms to attract electrons in a covalent bond, and it's a relative scale, where the difference between two atoms is measured in comparison to all other atoms in the periodic table.
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Correct Question:
Given the electronegativity values of C (2.5) and O (3.5), illustrate the bond polarity in a carbon monoxide molecule, CO, using delta notation.Group of answer choices
1. (δ-) C-O
2. (δ+)(δ+) C-O
3. (δ-)(δ+) C-O
4. (δ+)(δ-) C-O (δ-)
5. none of the above.
Consider the following equilibrated system: 2NO2(g) 2NO(g) + O2(g). If the Kp value is 0. 648, find the equilibrium pressure of the O2 gas if the NO2 gas pressure is 0. 520 atm and the PNO is 0. 300 atm at equilibrium
Considering the following equilibrated system: the equilibrium pressure of [tex]O_2[/tex] gas is approximately 1.944 atm.
In an equilibrated system, the equilibrium constant (Kp) expresses the ratio of the partial pressures of the products to the partial pressures of the reactants, with each raised to the power of their respective stoichiometric coefficients. The balanced equation for the given system is: [tex]2NO_2(g)[/tex](g) ⇌ [tex]2NO(g) + O_2(g).[/tex]
Given that the Kp value is 0.648, we can set up an expression for the equilibrium constant:
Kp = [tex](PNO)^2 * (PO_2) / (PNO_2)^2[/tex]
We are given the partial pressures of [tex]NO_2[/tex] and NO at equilibrium as 0.520 atm and 0.300 atm, respectively. Let’s assume the equilibrium pressure of O2 is “x” atm.
Substituting the given values into the expression, we have:
0.648 = [tex](0.300)^2 * x / (0.520)^2[/tex]
Simplifying the equation:
0.648 = (0.09 * x) / (0.2704)
0.648 = 0.3333 * x
X ≈ 1.944 atm
Therefore, the equilibrium pressure of [tex]O_2[/tex] gas is approximately 1.944 atm.
This indicates that at equilibrium, the partial pressure of [tex]O_2[/tex] is 1.944 atm, while the partial pressures of [tex]NO_2[/tex] and NO are 0.520 atm and 0.300 atm, respectively, in accordance with the given equilibrium constant (Kp) value.
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If it take 87 mL of 6. 4 M Ba(OH)2 solution to completely neutralize 5. 5 M of HI
solution, what is the volume of the Hl solution needed?
The concept of molarity (M) and the stoichiometry of the balanced chemical equation between Ba(OH)2 and HI. The balanced equation is Ba(OH)2 + 2HI -> BaI2 + 2H2O.
From the equation, we can see that 1 mole of Ba(OH)2 reacts with 2 moles of HI. First, we need to calculate the number of moles of Ba(OH)2 used:
Molarity (M) = moles of solute / volume of solution (L)
Rearranging the equation, moles of solute = Molarity × volume of solution (L)
Moles of Ba(OH)2 = 6.4 M × 0.087 L = 0.5568 moles
Since the stoichiometry of the balanced equation tells us that 1 mole of Ba(OH)2 reacts with 2 moles of HI, we can conclude that 0.5568 moles of Ba(OH)2 will react with (0.5568 × 2) = 1.1136 moles of HI.
Now, we can calculate the volume of the HI solution needed:
Volume of HI solution (L) = moles of HI / Molarity of HI
Moles of HI = 1.1136 moles
Molarity of HI = 5.5 M
Volume of HI solution = 1.1136 moles / 5.5 M = 0.2021 L or 202.1 mL Therefore, approximately 202.1 mL of the HI solution is needed to completely neutralize the 87 mL of 6.4 M Ba(OH)2 solution.
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a solution was made by dissolving 4.73g of sodium chloride in 51.9 g water. what is mole fraction of water in this solution
The mole fraction of water in this solution is 0.972 when a solution was made by dissolving 4.73g of sodium chloride in 51.9 g water.
To find the mole fraction of water in this solution, we first need to calculate the moles of sodium chloride and water in the solution.
The molar mass of sodium chloride is 58.44 g/mol, so the number of moles of sodium chloride in the solution is:
moles of NaCl = mass of NaCl / molar mass of NaCl
moles of NaCl = 4.73 g / 58.44 g/mol
moles of NaCl = 0.081 moles
The molar mass of water is 18.02 g/mol, so the number of moles of water in the solution is:
moles of water = mass of water / molar mass of water
moles of water = 51.9 g / 18.02 g/mol
moles of water = 2.88 moles
The mole fraction of water in the solution is:
mole fraction of water = moles of water / (moles of NaCl + moles of water)
mole fraction of water = 2.88 moles / (0.081 moles + 2.88 moles)
mole fraction of water = 0.972
Therefore, the mole fraction of water in this solution is 0.972.
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newly discovered compound called coenzyme U is isolated from mitochondria. Severa lines of evidence are presented advancing the claim that coenzyme U is previously unrecognized carrier in the electron transport chain. series of experiments has been performed to determine where in the electron transport chain coenzyme sits_ Which of the following the most convincing evidence that coenzyme U is part of the electron transport chain? a.When added to mitochondria suspension, coenzyme U is readily taken up by mitochondria: b.Removal of coenzyme U from mitochondria results in decreased rate of oxygen consumption:
c. Addition of NADH with coenzyme U to mitochondrial suspension caused rapid reduction of coenzyme U.
d. The rate of oxidation and reduction of coenzyme U in mitochondria is the same as the overall rate of electron transport: e.AIl other known coenzymes are part of the electron transport chain; so coenzyme U must be; too.
The most convincing evidence that coenzyme U is part of the electron transport chain is option d.
Option d presents a direct link between the oxidation and reduction of coenzyme U and the overall rate of electron transport. This indicates that coenzyme U is involved in the electron transfer process, and its presence is essential for the efficient functioning of the electron transport chain.
The other options also provide evidence that coenzyme U is involved in the electron transport chain, but they do not offer a direct link between coenzyme U and the overall rate of electron transport.
For example, option a shows that coenzyme U is readily taken up by mitochondria, but it does not prove that it is part of the electron transport chain. Similarly, option b indicates that the removal of coenzyme U results in decreased oxygen consumption, but it does not provide a direct link to electron transport.
Option c shows that coenzyme U is rapidly reduced when added with NADH, but this only suggests that it interacts with NADH, not that it is part of the electron transport chain. Option e is not a valid piece of evidence as it is based on a logical deduction rather than empirical data.
Based on the evidence presented, option d is the most convincing evidence that coenzyme U is part of the electron transport chain.
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calculate e°cell for the following reaction: 2 fe2 (aq) cd2 (aq) ↔ 2 fe3 (aq) cd (s)
I'll gladly help you calculate the E°cell for the given reaction. To do this, we'll use the Nernst equation and the standard reduction potentials for the two half-reactions involved. Here are the steps to calculate E°cell:
1. Identify the half-reactions:
Fe2+ (aq) → Fe3+ (aq) + e- (Oxidation half-reaction)
Cd2+ (aq) + 2e- → Cd (s) (Reduction half-reaction)
2. Find the standard reduction potentials (E°) for both half-reactions from a reference table:
E°(Fe3+/Fe2+) = +0.77 V
E°(Cd2+/Cd) = -0.40 V
3. Reverse the oxidation half-reaction's potential, as it needs to be an oxidation potential instead of a reduction potential:
E°(Fe2+/Fe3+) = -0.77 V
4. Add the standard potentials for both half-reactions to find E°cell:
E°cell = E°(Fe2+/Fe3+) + E°(Cd2+/Cd)
E°cell = -0.77 V + (-0.40 V)
E°cell = -1.17 V
The E°cell for the given reaction is -1.17 V. This indicates that the reaction is not spontaneous under standard conditions, as a positive E°cell would be required for a spontaneous reaction.
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using the provided data, determine the temperatures at which the following hypothetical reaction will be nonspontaneous under standard conditions a b → 2c d △s°rxn = -295.4 j/k △h°rxn = 100.4 kj
The reaction will be nonspontaneous at temperatures above 339.73 K under standard conditions.
To determine the temperatures at which the hypothetical reaction (a b → 2c d) will be nonspontaneous under standard conditions, we need to analyze the given data: ΔS°rxn = -295.4 J/K and ΔH°rxn = 100.4 kJ.
First, let's convert ΔH°rxn to J/mol for consistency: ΔH°rxn = 100.4 kJ * 1000 J/kJ = 100400 J/mol.
Now we'll use the Gibbs Free Energy equation: ΔG°rxn = ΔH°rxn - TΔS°rxn. The reaction will be nonspontaneous if ΔG°rxn > 0.
So, we need to find the temperature (T) at which ΔG°rxn > 0:
0 < ΔH°rxn - TΔS°rxn
0 < 100400 J/mol - T(-295.4 J/K)
T > 100400 J/mol / 295.4 J/K
T > 339.73 K
Therefore, the reaction will be nonspontaneous at temperatures above 339.73 K under standard conditions.
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Does trans-oleic acid have a higher or lower melting point than cis-oleic acid? Explain Which triacylglycerol yields more energy on oxidation: one containing three resides of linolenic acid or three residues of stearic acid?
Trans-oleic acid has a higher melting point than cis-oleic acid and a triacylglycerol containing three residues of stearic acid yields more energy upon oxidation compared to one containing three residues of linolenic acid.
Trans-oleic acid has a higher melting point than cis-oleic acid. This is because the trans configuration results in a more linear structure, allowing the molecules to pack more closely together, leading to stronger intermolecular forces and a higher melting point.
A triacylglycerol containing three residues of stearic acid yields more energy upon oxidation compared to one containing three residues of linolenic acid.This is because stearic acid is a saturated fatty acid, which means it has a higher carbon-to-hydrogen ratio, leading to more energy release upon oxidation. Linolenic acid, on the other hand, is an unsaturated fatty acid and has a lower carbon-to-hydrogen ratio, resulting in less energy release upon oxidation.
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Trans-oleic acid has a higher melting point than cis-oleic acid. Three residues of stearic acid yield more energy on oxidation than three residues of linolenic acid due to the higher number of carbon atoms and absence of double bonds.
Trans-oleic acid has a higher melting point than cis-oleic acid due to its straighter shape, which allows for closer packing and stronger intermolecular forces. In contrast, cis-oleic acid has a kink in its structure due to the cis double bond, which results in weaker intermolecular forces and a lower melting point.
Stearic acid has a higher number of carbon atoms (18) and lacks double bonds, making it a saturated fatty acid. Saturated fatty acids can pack more closely together, resulting in stronger intermolecular forces and a higher energy yield upon oxidation. In contrast, linolenic acid is an unsaturated fatty acid with three double bonds, making it a polyunsaturated fatty acid. The presence of double bonds causes kinks in the fatty acid chains, making it more difficult for them to pack together, resulting in weaker intermolecular forces and a lower energy yield upon oxidation.
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Which of the following is the weakest reducing agent?
a. C
r
3
+
(
a
q
)
b. K
(
s
)
c. C
a
2
+
(
a
q
)
d. C
r
(
s
)
e. F
−
(
a
q
)
The weakest reducing agent among the options given is Ca[tex]_{2}[/tex]+(aq). Option C is answer.
The strength of a reducing agent is determined by its ability to donate electrons and undergo oxidation. In this case, we can compare the reduction potentials of the species listed.
Cr[tex]_{3}[/tex]+(aq) is a stronger reducing agent than Ca[tex]_{2}[/tex]+(aq) because it has a higher tendency to donate electrons and get reduced. Similarly, Cr(s) is a stronger reducing agent than Ca[tex]_{2}[/tex]+(aq) because it has a greater tendency to donate electrons.
K(s) is a very strong reducing agent as it readily donates its electron, making it the strongest reducing agent among the options.
F−(aq) is also a strong reducing agent because it readily accepts electrons and gets reduced.
Option C is answer.
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one of the factors that influences the behavior of a gas sample is pressure. pressure can be expressed using different units, and it is important to be able to convert between them.
To convert pressure in atmospheres to Pascals write values down, use conversion factor and multiply given pressure by conversion factor.
One of the factors that influences the behavior of a gas sample is pressure. Pressure is the force exerted by the gas particles on the walls of its container, and it is influenced by factors like temperature and volume. In order to compare pressure values or perform calculations involving pressure, it's crucial to be able to convert between different units of pressure.
Common units for pressure include:
1. Pascal (Pa)
2. Atmosphere (atm)
3. Bar (bar)
4. Torr (torr) or millimeters of mercury (mmHg)
To convert between these units, you can use the following conversion factors:
1 atm = 101325 Pa
1 atm = 1.01325 bar
1 atm = 760 torr (or 760 mmHg)
Now, let's say you have a pressure value in atmospheres and you want to convert it to Pascals. Here's the step-by-step process:
1. Write down the given pressure value in atmospheres (e.g., 2 atm).
2. Use the conversion factor (1 atm = 101325 Pa).
3. Multiply the given pressure by the conversion factor (2 atm * 101325 Pa/atm).
After performing the calculation, you'll get the pressure value in Pascals (202650 Pa).
By following similar steps, you can convert pressure values between any of the mentioned units.
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a molecule containing a central atom with sp3 hybridization has a(n) ________ electron geometry. a) linear b) trigonal pyramidal c) seesaw d) tetrahedral e) bent 4) using the vse
A molecule with a central atom exhibiting sp3 hybridization has a tetrahedral electron geometry.
Option (D)
This is because the sp3 hybridization involves the combination of one s and three p orbitals, resulting in four hybrid orbitals arranged in a tetrahedral geometry around the central atom. Each of these hybrid orbitals can accommodate a pair of electrons, which gives rise to the tetrahedral electron geometry.
The VSEPR (Valence Shell Electron Pair Repulsion) theory is a useful tool for predicting the shape of molecules based on their electron pair geometry. According to this theory, electron pairs repel each other and tend to stay as far apart as possible, leading to specific molecular geometries. For a molecule with a tetrahedral electron geometry, the VSEPR model predicts a corresponding tetrahedral molecular shape.
It is important to note that while the electron geometry is tetrahedral, the molecular shape may differ depending on the presence of lone pairs of electrons. For example, a tetrahedral electron geometry with one lone pair would result in a trigonal pyramidal molecular shape, while a tetrahedral electron geometry with two lone pairs would result in a bent molecular shape. Option (D)
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A molecule with a central atom exhibiting sp3 hybridization has a tetrahedral electron geometry. Option (D)
This is because the sp3 hybridization involves the combination of one s and three p orbitals, resulting in four hybrid orbitals arranged in a tetrahedral geometry around the central atom. Each of these hybrid orbitals can accommodate a pair of electrons, which gives rise to the tetrahedral electron geometry.
The VSEPR (Valence Shell Electron Pair Repulsion) theory is a useful tool for predicting the shape of molecules based on their electron pair geometry. According to this theory, electron pairs repel each other and tend to stay as far apart as possible, leading to specific molecular geometries. For a molecule with a tetrahedral electron geometry, the VSEPR model predicts a corresponding tetrahedral molecular shape.
It is important to note that while the electron geometry is tetrahedral, the emolecular shap may differ depending on the presence of lone pairs of electrons. For example, a tetrahedral electron geometry with one lone pair would result in a trigonal pyramidal molecular shape, while a tetrahedral electron geometry with two lone pairs would result in a bent molecular shape. Option (D)
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The standard free energy of formation of ammonia is -16.5 Kj/mol. What is the value of K for the reaction below at 575.0 K?
N2(g) + 3 H2(g) --- 2 NH3(g)
the value of K for the reaction below at 575.0 K is K= 1.4 x 10^2 at 575 K for N2(g) + 3 H2(g) ⇌ 2 NH3(g) with ΔG°f = -16.5 KJ/mol.
The value of K for the given reaction at 575 K can be calculated using the standard free energy change of formation (ΔG°f) of ammonia.
According to the equation ΔG° = -RT ln(K), where R is the gas constant and T is the temperature in Kelvin, we can rearrange the equation to solve for K.
Therefore, K = e^(-ΔG°/RT). Substituting the given values, K = e^(-(-16.5*10^3)/(8.314*575)) = 1.4 x 10^2.
Hence, the equilibrium constant K for N2(g) + 3 H2(g) ⇌ 2 NH3(g) at 575 K is 1.4 x 10^2.
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To find the value of K for the reaction, we need to use the equation:
ΔG° = -RTlnK
Where ΔG° is the standard free energy of formation, R is the gas constant (8.314 J/mol K), T is the temperature in Kelvin, and K is the equilibrium constant.
First, we need to convert the standard free energy of formation from Kj/mol to J/mol:
ΔG° = -16.5 Kj/mol x 1000 J/Kj = -16,500 J/mol
Next, we need to calculate the value of ΔG at 575.0 K. To do this, we use the equation:
ΔG = ΔH - TΔS
Where ΔH is the enthalpy of the reaction, ΔS is the entropy of the reaction, and T is the temperature in Kelvin. We can use the following values for ΔH and ΔS:
ΔH = -92.4 kJ/mol
ΔS = -198.4 J/mol K
ΔG = (-92.4 kJ/mol x 1000 J/kJ) - (575.0 K x -198.4 J/mol K) = -49,933 J/mol
Now that we have ΔG at 575.0 K, we can use the equation:
ΔG° = -RTlnK
To solve for K:
K = e^(-ΔG°/RT) = e^(-(-16,500 J/mol)/(8.314 J/mol K x 575.0 K)) = 7.7 x 10⁸
Therefore, the value of K for the reaction N₂(g) + 3 H₂(g) ↔ 2 NH₃(g) at 575.0 K is 7.7 x 10⁸.
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The density of a 3.539 M HNO3 aqueous solution is 1.150 g/ml. at 20°C. Calculate the molality of the solution. The molar mass of HNO3 is 63.02 g/mol. a. 3.946 m b. 3.818 m O c. 5.252 m O d. 3.077 m Moving to another question will save this response.
The molality of the 3.539 M HNO3 aqueous solution is 0.22299 m.
To calculate the molality of the 3.539 M HNO3 aqueous solution, we need to first convert the given density from g/mL to kg/L. We can do this by dividing 1.150 g/mL by 1000, giving us 0.001150 kg/L.
Next, we can use the formula for molality, which is moles of solute per kilogram of solvent. We know the molar mass of HNO3 is 63.02 g/mol, so we can calculate the moles of HNO3 in 1 L of solution as follows:
3.539 moles/L x 63.02 g/mol = 222.99 g/L
To convert this to kg/L, we divide by 1000:
222.99 g/L ÷ 1000 = 0.22299 kg/L
Finally, we can calculate the molality by dividing the moles of solute by the kilograms of solvent:
molality = 0.22299 mol ÷ 1 kg = 0.22299 m
Therefore, the molality of the 3.539 M HNO3 aqueous solution is 0.22299 m. None of the answer choices match, so there may be a mistake in the question or in the answer choices provided.
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The molality of the solution, given that the density of the 3.539 M HNO₃ aqueous solution is 1.150 g/mL at 20 °C is 3.818 M (option B)
How do I determine the molality of the solution?First, we shall determine the mass of the solution. Details below:
Density of solution = 1.150 g/mLVolume of solution = 1000 mLMass of solution =?Mass of solution = density × volume
Mass of solution = 1.15 × 1000
Mass of solution = 1150 g
Next, we shall obtain the mole of HNO₃ in the solution. Details below:
Molarity of HNO₃ = 3.539 MVolume of solution = 1000 mL = 1 LMole of HNO₃ =?Mole = molarity × volume
Mole of HNO₃ = 3.539 × 1
Mole of HNO₃ = 3.539 moles
Next, we shall obtain the mass of the water. Details below:
Mole of HNO₃ (n) = 3.539 molesMolar mass of HNO₃ (M) = 63.02 g/molMass of HNO₃ = n × M = 3.539 × 63.02 = 223.03 gMass of solution = 1150 gMass of water =?Mass of water = Mass of solution - Mass of HNO₃
Mass of water = 1150 - 223.03
Mass of water = 926.97 g
Finally, we shall determine the molality of the solution. Details below:
Mole of HNO₃ = 3.539 molesMass of water = 926.97 g = 926.97 / 1000 = 0.92697 KgMolality of solution =?Molality = mole / mass of water (in Kg)
Molality of solution = 3.539 / 0.92697
Molality of solution = 3.818 M (option B)
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Propose a structure consistent with the following spectral data for a compound C8H18O2:
IR: 3350 cm–1
1H NMR: 1.24 δ (12 H, singlet); 1.56 δ (4 H, singlet); 1.95 δ (2 H, singlet)
The proposed structure for the compound is CH₃-CH₂-CH₂-CH₂-CH₂-CH₂-CH₂-OCOCH₃.
Based on the spectral data provided, we can propose the following structure for the compound C₈H₁₈O₂:
CH₃-CH₂-CH₂-CH₂-CH₂-CH₂-CH₂-OCOCH₃.
The IR spectrum shows a strong peak at 3350 cm⁻¹, which indicates the presence of an -OH group. The NMR spectrum shows three distinct signals at 1.24 δ, 1.56 δ, and 1.95 δ, which indicates the presence of three different types of protons.
The signal at 1.24 δ is a singlet with 12 equivalent protons, which indicates the presence of eight methylene (-CH₂-) groups. The signal at 1.56 δ is also a singlet with four equivalent protons, which indicates the presence of two methylene groups. The signal at 1.95 δ is a singlet with two equivalent protons, which indicates the presence of a methyl (-CH₃) group.
Putting these pieces of information together, we can propose a structure for the compound that contains an eight-carbon chain with an -OH group attached to a methylene group at one end and an ester group (-OCOCH0₃) attached to the other end. The structure is consistent with the spectral data and has the following formula: C₈H₁₈O₂
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2. What physiological adaptations cause training- induced changes in VO2max? 3. What specific physiological adaption would cause an increase in in the first 2 weeks of training? VO2max 4. How would VO2max results differ between grade exercise tests (GXT) on a treadmill vs. cycle ergometer? Why? 5. Is VO2max (by itself) the best indicator of endurance performance? Why or why not? What other factors influence endurance performance?
Physiological adaptations such as increased cardiac output, capillary density, and muscle oxidative capacity cause training-induced changes in VO₂ max.
VO₂ max is the maximum amount of oxygen that an individual can utilize during exercise and is a critical measure of endurance capacity. Training-induced adaptations can increase VO₂ max by improving the delivery and utilization of oxygen in the body. These adaptations include an increase in cardiac output, which is the amount of blood the heart pumps per minute, and an increase in capillary density, which enhances oxygen delivery to the muscles.
Additionally, training can increase muscle oxidative capacity, which enables muscles to use oxygen more efficiently during exercise. This can lead to an increase in VO₂ max within the first two weeks of training due to improved oxygen delivery to the muscles. VO₂ max results may differ between GXT on a treadmill vs. cycle ergometer because the type of exercise and muscle recruitment patterns may affect oxygen utilization.
While VO₂ max is an important measure of endurance performance, other factors such as lactate threshold, economy of movement, and mental toughness also influence performance.
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7. What additional reactant is required for oxidation of polyunsaturated fatty acids compared to saturated fatty acids? A. Biotin B.O2 C. NADPH D. ATP E. FAD+
The additional reactant required for oxidation of polyunsaturated fatty acids compared to saturated fatty acids is Biotin.
Biotin is a coenzyme that helps in the carboxylation of fatty acids, which is necessary for their oxidation. Polyunsaturated fatty acids have more double bonds than saturated fatty acids, which makes them more flexible and prone to structural changes.
Therefore, biotin plays a crucial role in the oxidation of these flexible fatty acids. On the other hand, saturated fatty acids have a more rigid structure, making them less dependent on biotin for their oxidation.
In summary, biotin is essential for the oxidation of polyunsaturated fatty acids due to their structural properties, while saturated fatty acids require less biotin for oxidation.
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Consider the following rate law expression: rate = k[A][B]2. If the concentration of A is tripled and the concentration of B is reduced by half, what is the resulting change in the reaction rate?The rate is increased by 3/2.The rate is reduced by 3/4.The rate stays the same.The rate is doubled.The rate is reduced by 1/2.
If the concentration of A is tripled and the concentration of B is reduced by half, the resulting change in the reaction rate is an increase of 3/2.
The rate law expression rate = k[A][B]2 tells us that the rate of the reaction depends on the concentrations of both reactants, A and B, and that B has a greater impact on the rate than A.
Now, if the concentration of A is tripled, it means that the new concentration of A is three times the original concentration. Similarly, if the concentration of B is reduced by half, it means that the new concentration of B is half the original concentration.
Substituting these new values into the rate law expression gives us:
new rate = k[(3[A])/2][(B)/2]2
Simplifying this expression gives us:
new rate = (9/4)k[A][B]2
Comparing this expression with the original rate law expression, we see that the new rate is (9/4) times the original rate. Therefore, the resulting change in the reaction rate is that the rate is increased by 3/2.
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If the concentration of A is tripled and the concentration of B is reduced by half, the resulting change in the reaction rate will increase by 3/2, as the rate law expression is dependent on the concentration of A and the square of the concentration of B.
The given rate law expression shows that the reaction rate is directly proportional to the concentration of A and the square of the concentration of B. Therefore, if the concentration of A is tripled, the reaction rate will also triple. Similarly, if the concentration of B is halved, the reaction rate will decrease by a factor of 4 (since the concentration is squared in the rate law expression). As a result, the net effect on the reaction rate will be an increase by 3/2 (3/1.5) when the concentration of A is tripled and the concentration of B is halved. This is because the increase in the concentration of A will have a larger effect on the reaction rate than the decrease in the concentration of B.
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Rank the following elements in order of increasing ionization energy: Ge,Rb,S,Ne A. Ge
The correct order of increasing ionization energy for the given elements is:
Ne < Rb < S < Ge.
The amount of energy required for an isolated, gaseous molecule in the ground electronic state to absorb in order to discharge one electron and produce a cation is known as the ionisation energy. The amount of energy required for every atom in a mole to lose one electron is often given as kJ/mol.
First ionisation energy normally rises from left to right over a period on the periodic table. The outermost electron is more tightly connected to the nucleus as a result of the increased nuclear charge.
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a 1.3×10−6mol sample of sr(oh)2 is dissolved in water to make up 25.0 ml of solution. what is the ph of the solution at 25.0∘c
The pH of the solution is 10.98 at 25°C.
When Sr(OH)2 is dissolved in water, it dissociates to form Sr2+ and 2OH- ions. The concentration of each ion in the resulting solution can be calculated using the initial amount of Sr(OH)2 and the volume of the solution.
First, we need to determine the concentration of Sr2+ and OH- ions in the solution. Since each Sr(OH)2 molecule dissociates into two OH- ions and one Sr2+ ion, the concentration of Sr2+ in the solution will be half of the concentration of OH- ions.
The initial amount of Sr(OH)2 in the solution is:
moles = 1.3×10^-6 mol
The volume of the solution is:
volume = 25.0 ml = 0.0250 L
Using this information, we can calculate the concentration of OH- ions:
[OH-] = 2 × moles / volume
= 2 × 1.3×10^-6 mol / 0.0250 L
= 1.04 × 10^-4 M
Since the concentration of Sr2+ ions is half that of OH- ions, we have:
[Sr2+] = 0.5 × [OH-]
= 0.5 × 1.04 × 10^-4 M
= 5.20 × 10^-5 M
Now, we can use the ion product constant for water (Kw) to calculate the pH of the solution:
Kw = [H+][OH-]
= 1.0 × 10^-14 at 25°C
At 25°C, Kw = 1.0 × 10^-14, so:
pH = -log[H+]
= -log(Kw/[OH-])
= -log(1.0 × 10^-14 / 1.04 × 10^-4)
= 10.98
Therefore, the pH of the solution is 10.98 at 25°C.
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