A student burns 20 grams of methane in the presence of excess oxygen to produce 43 grams of
water according to the equation below.
CH4 +20₂→ CO₂ + 2H₂O
What is the theoretical yield of the reaction? Did the reaction produce as much as expected
based on calculations? Why might we have collected less that we would expect to produce with
this reaction?
Answer with at least 3 complete sentences.

The pH of the solution is 4.9.

The pH and pOH of a solution are related by the equation:

pH + pOH = 14

Therefore, if the pOH of a solution is 9.1, we can calculate its pH as:

pH = 14 - pOH

pH = 14 - 9.1

pH = 4.9

So, the pH of the solution is 4.9. The pH scale is a logarithmic scale that measures the acidity or basicity of a solution. A pH of 7 is neutral, while a pH below 7 is acidic and a pH above 7 is basic. In this case, the pH is below 7, which means the solution is acidic.

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Identifying areas with widespread precipitation and locating a weather front. Since you haven't provided a specific map or image, how to approach these tasks using the given terms.

Part C: To identify areas with the most widespread precipitation, look for large patches of color on a weather map or satellite image. These colors typically represent different levels of precipitation intensity. The most widespread precipitation will be in areas where these colored patches cover a large geographic region.

Part D: To locate a weather front, look for a line of precipitation on the map or image. This line often represents a boundary between two air masses with different temperatures and humidity levels. To determine the front's direction, you can observe the movement of the line over time, either by analyzing a series of images or by referring to weather forecasts. The front will typically move in the direction that the air masses are being pushed by prevailing winds.

Please refer to a specific weather map or satellite image and apply these steps to find the areas with widespread precipitation and the location and direction of a weather front.

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A reaction must be spontaneous if its occurrence is exothermic with an increase in entropy.

For a reaction to be spontaneous, two factors are considered: enthalpy change (ΔH) and entropy change (ΔS). A spontaneous reaction usually has a negative ΔH, indicating that it is exothermic (releases heat).

Additionally, a spontaneous reaction has a positive ΔS, meaning there is an increase in entropy (disorder) in the system. The combination of these two factors, along with temperature (T), determines the Gibbs free energy change (ΔG), where ΔG = ΔH - TΔS.

A negative ΔG value signifies that the reaction is spontaneous. Therefore, a reaction with an exothermic occurrence and an increase in entropy is more likely to be spontaneous.

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The difference in temperature from Saturday to Sunday is 9 degrees Celsius. This means that the temperature increased by 9 degrees from Saturday to Sunday.

To show the difference in temperature from Saturday to Sunday, we can use the equation:

Difference = Sunday temperature - Saturday temperature

Given that the temperature on Saturday is -13° and on Sunday it is -4°, we can calculate the difference in temperature using the above equation as follows:

Difference = -4° - (-13°)

Difference = -4° + 13°

Difference = 9°

The number line is a graphical representation of numbers where we can visualize their position relative to each other. Starting from -13° on the number line and moving 9 units to the right, we reach -4°, which represents the temperature on Sunday. This visualization confirms that the difference between the two temperatures is 9 degrees.

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Answer:

An electron has a negative charge therefore, losing the electron will cause the atom to be a positive ion. An ion is an atom where the number of protons does not equal the number of electrons.

The mass of chlorine needed to react with 0.175 g of gold is 94.52 mg.

The balanced chemical reaction is :
2 Au + 3 Cl₂ → 2 AuCl₃

Relative atomic masses: Cl = 35.5 and Au = 197

Converting the mass of gold to moles:
0.175 g Au * (1 mol Au / 197 g Au) = 0.00088756 mol Au

The number of moles of Cl₂ needed to react with the gold is:
=0.00088756 mol Au * (3 mol Cl₂ / 2 mol Au) = 0.00133134 mol Cl₂

Converting the moles of Cl₂ to grams:
=0.00133134 mol Cl₂ * (2 x 35.5 g Cl₂ / 1 mol Cl₂) = 0.09452 g Cl₂

Converting the mass of Cl₂ from grams to milligrams:
=0.09452 g Cl₂ * (1000 mg / 1 g) = 94.52 mg Cl₂

Therefore, the mass of chlorine needed to react with 0.175 g of gold is approximately 94.52 mg.

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The volume of the gas-filled balloon at STP would be 36.7 L.

To solve this problem, we can use the combined gas law, which relates the pressure, volume, and temperature of a gas:

(P1V1)/T1 = (P2V2)/T2

where P1, V1, and T1 are the initial pressure, volume, and temperature, respectively, and P2, V2, and T2 are the final pressure, volume, and temperature, respectively.

At STP (standard temperature and pressure), the temperature is 273 K and the pressure is 1 atm. So we have:

(P1V1)/T1 = (P2V2)/T2

(1.5 atm x 30.0 L)/313 K = (1 atm x V2)/273 K

Solving for V2:

V2 = (1.5 atm x 30.0 L x 273 K)/(1 atm x 313 K)

V2 = 36.7 L

Therefore, the volume of the gas-filled balloon at STP would be 36.7 L.

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It is anticipated that temperatures in the lower atmosphere would rise as carbon dioxide ([tex]CO_2[/tex]) levels in the atmosphere continue to rise. This is because CO2, a greenhouse gas, keeps heat from going back into space and instead stores it in the atmosphere. More heat will be trapped when [tex]CO_2[/tex] concentration rises, producing a warming effect. The Greenhouse Effect is a common name for this phenomenon.

According to predictions made by the Intergovernmental Panel on Climate Change (IPCC), a doubling of atmospheric [tex]CO_2[/tex] concentrations might lead to a 1.5–4.5 degree Celsius rise in global temperature. Among other things, this temperature rise may have a profound effect on ecosystems, weather patterns, and sea levels.

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The DART system and sensors have several advantages over seismometers and coastal tide gauges in measuring tsunami-related events. Three advantages are Real-time measurement, Wide coverage and High accuracy.

Real-time measurement: The DART system provides real-time measurements of the height and speed of waves in the open ocean, whereas seismometers and coastal tide gauges only measure the arrival time and amplitude of waves at a specific location. Real-time measurements allow for more accurate and timely predictions of tsunami-related events, enabling earlier warning and faster response times.

Wide coverage: The DART system covers a larger area than seismometers and coastal tide gauges, allowing for more comprehensive monitoring of oceanic waves. The wider coverage allows for more accurate prediction of the direction, speed, and strength of tsunamis, reducing the risk of false alarms and missed warnings.

High accuracy: The DART system is designed to measure the height and speed of waves with high accuracy, providing detailed information on the magnitude and severity of tsunamis. This level of accuracy can improve predictions by providing more precise estimates of the extent of damage and the areas at risk, enabling more effective disaster planning and response.

Overall, the DART system and sensors offer significant advantages over traditional seismometers and coastal tide gauges, providing more accurate and timely predictions of tsunami-related events, enabling faster response times, and reducing the risk of false alarms and missed warnings.

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Ma is the equivalent of an element that belongs to the [tex]3_r_d[/tex] column of the periodic table, while Tw is the equivalent of an element that belongs to the 6th column of the periodic table in this alternate dimension.

What is Compound?

In chemistry, a compound is a substance composed of two or more different types of elements chemically bonded together in a fixed proportion. The elements in a compound are combined in a way that results in a new substance with different chemical and physical properties from the individual elements that make it up.

Let's assume that Ma has a charge of +3 and Tw has a charge of -2 in this alternate dimension. To balance the charges, we need 3 Tw atoms for every 2 Ma atoms.

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The concentration of pesticide remaining after 62.0 minutes at 25°C is 0.0191 M.

The first-order rate law for a reaction can be expressed as:

[tex]ln([A]/[A]₀) = -kt[/tex]

Where [A] is the concentration of the reactant at any given time, [A]₀ is the initial concentration, k is the rate constant, and t is the time elapsed.

Using the given rate constant of [tex]6.40 × 10^(-3) min^(-1)[/tex]and the initial concentration of 0.0314 M, we can plug in the values and solve for [A] after 62.0 minutes:

[tex]ln([A]/0.0314) = -(6.40 × 10^(-3) min^(-1)) × (62.0 min)[/tex]

Solving for [A], we get:

[tex][A] = 0.0314 × e^(-(6.40 × 10^(-3) min^(-1)) × (62.0 min))[/tex]

[A] = 0.0191 M

Therefore, the concentration of pesticide remaining after 62.0 minutes at 25°C is 0.0191 M.

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To calculate the energy of a rogue wave with an amplitude of 15 meters, we can use the following formula:

E = 0.5ρAv^2

where E is the energy of the wave, ρ is the density of the water, A is the amplitude of the wave, and v is the velocity of the wave.

Assuming the density of water is 1000 kg/m^3 and the velocity of the wave is the standard gravitational acceleration of 9.81 m/s^2 (since rogue waves are caused by the interaction of multiple waves), we can calculate the energy of the rogue wave:

E = 0.5 x 1000 kg/m^3 x π x (15 m)^2 x (9.81 m/s^2)^2

E = 1.22 x 10^9 J

Therefore, the energy of a rogue wave with an amplitude of 15 meters is approximately 1.22 x 10^9 joules.

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From the Electron Configuration of Mystery Elements:

Mystery element A has an electron configuration of 2-8-18-7, which means it has 7 valence electrons. Based on this, it would be reactive because it only needs one more electron to complete its outermost shell of eight electrons, which is the stable configuration of noble gases. This is supported by the PPT slide evidence, which states that elements with fewer than 4 or more than 7 valence electrons tend to be reactive.

Mystery element D has an electron configuration of 2-8-8-2, which means it has 2 valence electrons. Based on this, it would be reactive because it only needs to lose or gain two electrons to complete its outermost shell. This is also supported by the PPT slide evidence, which states that elements with 1-3 valence electrons tend to lose electrons to form positive ions, while elements with 5-7 valence electrons tend to gain electrons to form negative ions. Therefore, mystery element D could either form a positive ion by losing two electrons or form a negative ion by gaining six electrons.

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the concentration of sulfate ion when the precipitation of barium sulfate begins is 1.07×10^-8 M.

To determine the formula of the substance that precipitates first, we need to determine which combination of ions will form an insoluble compound first. We can do this by considering the solubility rules for common ionic compounds.

Calcium acetate dissociates into Ca2+ and CH3COO- ions in solution, while barium nitrate dissociates into Ba2+ and NO3- ions. Ammonium sulfate, when added to the solution, will dissociate into NH4+ and SO42- ions.

The possible combinations of ions that can form insoluble compounds are:

- Ca2+ and SO42- form CaSO4, which is insoluble
- Ba2+ and SO42- form BaSO4, which is insoluble

According to the solubility rules, calcium sulfate (CaSO4) is slightly soluble in water, while barium sulfate (BaSO4) is insoluble. Therefore, the substance that precipitates first is barium sulfate (BaSO4).

To determine the concentration of sulfate ion when the precipitation first begins, we need to calculate the product of the concentrations of barium ion and sulfate ion, and compare it to the solubility product constant (Ksp) for barium sulfate.

The balanced chemical equation for the precipitation reaction is:

Ba(NO3)2 + (NH4)2SO4 → BaSO4↓ + 2NH4NO3

The Ksp expression for barium sulfate is:

Ksp = [Ba2+][SO42-]

At the point when precipitation begins, the barium and sulfate ion concentrations will be equal to each other, so we can use the concentration of barium ion to calculate the concentration of sulfate ion:

[Ba2+] = 1.03×10^-2 M

Ksp for barium sulfate is 1.1×10^-10 at 25°C.

Therefore, we can calculate the concentration of sulfate ion:

Ksp = [Ba2+][SO42-]

1.1×10^-10 = (1.03×10^-2 M)([SO42-])

[SO42-] = 1.07×10^-8 M

Therefore, the concentration of sulfate ion when the precipitation of barium sulfate begins is 1.07×10^-8 M.
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When water is boiling :B. the molecules at the surface of the liquid evaporate first.

a. This is because the heat energy is transferred to the water from the bottom, causing the water molecules to gain energy and move faster. As the water molecules move faster, they collide with each other and break the intermolecular forces that hold them together. The water molecules at the surface have weaker intermolecular forces compared to those in the bulk of the liquid, which means they can more easily overcome these forces and evaporate.

b. The part of a liquid molecule that usually has the highest kinetic energy is the part that is moving the fastest. In a water molecule, this would be the oxygen atom, as it is larger and has more electrons than the hydrogen atoms. The oxygen atom therefore has a greater mass and a larger electron cloud, which allows it to move more quickly than the hydrogen atoms.

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The total energy absorbed by a 500 g sample of red river ice when it is brought indoors and melted from -40°C to 25°C is 218,250 joules. This includes the energy required to raise the temperature of the ice, melt the ice, and raise the temperature of the resulting liquid water.

To calculate the total energy absorbed by the ice sample, we need to consider the different processes involved in the transition from ice at -40°C to liquid water at 25°C.

First, we need to calculate the energy required to raise the temperature of the ice from -40°C to 0°C:

Q1 = m × cice × ΔT1

Q1 = 500 g × 2.09 J/gK × (0°C - (-40°C))

Q1 = 41800 J

Next, we need to calculate the energy required to melt the ice at 0°C:

Q2 = m × ΔHfusion

Q2 = 500 g × 6.02 kJ/mol ÷ 18.02 g/mol

Q2 = 166 kJ

Then, we need to calculate the energy required to raise the temperature of the water from 0°C to 25°C:

Q3 = m × cwater × ΔT2

Q3 = 500 g × 4.18 J/gK × (25°C - 0°C)

Q3 = 10450 J

Finally, we add up the three energy values to get the total energy absorbed by the ice sample:

Qtotal = Q1 + Q2 + Q3

Qtotal = 41800 J + 166000 J + 10450 J

Qtotal = 218250 J

Therefore, the total energy absorbed by the ice sample is 218250 joules (J).

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The final pressure of the gas is 1,430 mmHg.

Using the combined gas law, we can relate the initial pressure, volume, and temperature to the final pressure and volume:

(P₁V₁)/T₁ = (P₂V₂)/T₂

where P₁, V₁, and T₁ are the initial pressure, volume, and temperature, and P₂ and V₂ are the final pressure and volume.

Plugging in the given values, we get:

(850 mmHg x 1.5 L)/288 K = (P₂ x 2.5 L)/308 K

Solving for P₂, we get:

P₂ = (850 mmHg x 1.5 L x 308 K)/(2.5 L x 288 K) = 1430 mmHg

Therefore, 1,430 mmHg is the final pressure of the gas.

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The pH of the NaOH solution prepared to react with the pennies is 14.550.

To determine the molarity of the NaOH solution prepared to react with the pennies, follow these steps:

1. Calculate the moles of NaOH: Divide the mass of NaOH by its molar mass (142.1 g / 39.997 g/mol) = 3.553 moles of NaOH.

2. Calculate the volume of the solution: Convert the volume from mL to L (1000.0 mL * (1 L / 1000 mL)) = 1.000 L.

3. Calculate the molarity: Divide the moles of NaOH by the volume of the solution (3.553 moles / 1.000 L) = 3.553 M.

The molarity of the NaOH solution prepared to react with the pennies is 3.553 M.

To determine the pH of the solution:

1. Use the formula: pH = -log[H+], where [H+] represents the concentration of hydrogen ions in the solution.

2. Since NaOH is a strong base, it dissociates completely in water. The concentration of OH- ions is equal to the molarity of NaOH (3.553 M).

3. Calculate the pOH: pOH = -log[OH-] = -log(3.553) = -0.550.

4. Convert pOH to pH: pH = 14 - pOH = 14 - (-0.550) = 14.550.

The pH of the NaOH solution prepared to react with the pennies is 14.550.

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Among the halogens, [tex]I2[/tex] has the lowest boiling point.

The boiling point of a substance is influenced by the strength of its intermolecular forces, which are the forces that hold molecules together. The halogens belong to the same group in the periodic table and have similar electronic configurations.

The boiling point increases with increasing molecular weight because the intermolecular forces increase with the size of the molecules.

The strength of the intermolecular forces depends on the type of attractive forces between the molecules. Among the halogens, the strength of the intermolecular forces increases with increasing polarity of the molecule.

Fluorine is the most electronegative of the halogens and has the smallest atomic size. Due to its high electronegativity, it has the strongest dipole-dipole interaction between its molecules, leading to the highest boiling point among the halogens.

On the other hand, iodine has the weakest intermolecular forces, leading to the lowest boiling point among the halogens. Therefore, among the halogens, I2 has the lowest boiling point.

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111900g  is the weight of an object that has the area of 74.6 m² and exerts a pressure of 1500 N/m².

Weight being a force The SI unit for weight is Newton (N), which also happens to be the same as the SI unit for force. When we look at how weight is expressed, we can see how it depends on both mass as well as the acceleration caused by gravity; while the mass might not vary from one location to another, the acceleration caused by gravity does.

Pressure = thrust/ area

              = weight/ area

1500  = weight/ 74.6

weight = 111900g

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ans.1

blank 1 = 4

blank 2 = 4

blank 3 = 1

blank 4 = 8

ans.2

blank 1 = 10

blank 2 = 15

blank 3 = 1

blank 4 = 30

ans.3

blank 1 =  1

blank 2 = 2

blank 3 = 2

blank 4 = 1

blank 5 =2

In B8, enter the custom transaction number function: `=C8&D8&LEFT(E1,1)`. Use Auto Fill to copy it down column B.

In G8, enter the nested function: `=IF(AND(E8="Credit",F8>=4000),"Flag","")`. Auto Fill it down column G.

In D5, create a data validation list with Quantity, Payment Type, and Amount.

In B5, type Trans# 30038C. In D5, select Quantity.

In F5, enter the nested lookup function: `=IF(D5="Quantity",VLOOKUP(B5,C8:F32,2,FALSE),IF(D5="Payment Type",VLOOKUP(B5,C8:F32,3,FALSE),IF(D5="Amount",VLOOKUP(B5,C8:F32,4,FALSE),"")))`.

Follow these steps to achieve the desired result in your Sales worksheet.

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During alpha decay, atomic nuclei emit alpha particles, which are helium-4 nuclei composed of two protons and two neutrons. So, during alpha decay, the total mass of the reactants is equal to the mass of the main nucleus before decay.

In beta-plus decay, also called positron emission, protons in the nucleus are converted into neutrons, and positrons and neutrinos are emitted. Since the mass of a positron is very small compared to the mass of a proton or neutron, the total mass of the reactants in beta and decay is very close to the mass of the parent nucleus before decay.

Beta -mm is also known as electrons or negatively, and the nucleus neutron is transformed into protons and electrons and is produced by antizatinrino. Because the electronic mass is very small compared to the mass of protons or neutrons, the total mass of the minimum minimum minimum reagent is very close to the body of the body.

Generally, the total mass of the reactants in a fission process is very close to the mass of the parent nucleus before fission, because the mass of the particles released during fission is much smaller than the mass of the parent nucleus. However, due to the conservation of energy and momentum, there can be slight differences in mass between the reactants and the decay products, called mass defects.

This mass defect is converted into energy according to Einstein's famous equation E = mc². where E is the energy released, m is the mass defect, and c is the speed of light.

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The mass of H₂ used in the reaction, given that 2.75 g of CO was inserted is 0.39 grams

The mass of H₂ used in the reaction can be obtained as illustrated below:

Balanced equation:

CO + 2H₂ -> CH₃OH

From the balanced equation above,

28 grams of CO required 4 grams of H₂

Therefore,

2.75 grams of CO will require = (2.75 grams × 4 grams) / 28 grams = 0.39 grams of H₂

Thus, we can conclude that the mass of H₂ used in the reaction is 0.39 grams

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To neutralize 100.0ml of a 2.5 M solution of H2SO4, you will need 28.055 grams of KOH.

To neutralize 100.0ml of a 2.5 M solution of H2SO4, you will need to add a certain amount of KOH, which will react with the H2SO4 to form water and a salt. The goal of this process is to achieve a neutral pH of 7, indicating that the acid and base have been completely reacted.

To calculate how many grams of KOH are needed, you first need to determine the number of moles of H2SO4 present in the solution. This can be done using the formula:

moles = concentration (M) x volume (L)

Plugging in the values, we get:

moles H2SO4 = 2.5 M x 0.100 L = 0.250 moles

Since H2SO4 is a diprotic acid, meaning it can donate two hydrogen ions, it will require twice the amount of KOH to neutralize. Therefore, we need to double the number of moles of H2SO4 to get the number of moles of KOH needed:

moles KOH = 2 x 0.250 moles = 0.500 moles

Now we can use the formula for finding the mass of a compound using its moles and molar mass:

mass = moles x molar mass

The molar mass of KOH is 56.11 g/mol, so we can plug in the values and solve for the mass of KOH needed:

mass KOH = 0.500 moles x 56.11 g/mol = 28.055 g

Therefore, to neutralize 100.0ml of a 2.5 M solution of H2SO4, you will need 28.055 grams of KOH.

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The age of the rock is approximately 2.6 billion years.

The fact that the rock contains one-fourth of its original amount of potassium-40 means that three-quarters of the original potassium-40 has decayed.

Since the half-life of potassium-40 is 1.3 billion years, this means that the rock has gone through two half-lives of decay.

To calculate the age of the rock, we can use the following formula:

age = number of half-lives x half-life

In this case, the number of half-lives is 2 and the half-life is 1.3 billion years. Plugging these values into the formula, we get:

age = 2 x 1.3 billion years

age = 2.6 billion years

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The central atom of a molecule that exceeds the octet rule must come from period 3 or below.

This is because elements in these periods have empty d-orbitals available for hybridization, which allows them to form more than four covalent bonds and exceed the octet rule.

Examples of such elements include sulfur (S), phosphorus (P), and chlorine (Cl). Elements in higher periods, such as xenon (Xe) and radon (Rn), can also exceed the octet rule but are relatively rare in organic chemistry.

It is important to note that not all atoms follow the octet rule, and some can have fewer than eight electrons in their valence shell due to their unique electronic configurations.

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The object absorbed 356.4 J of heat energy.

To calculate the amount of heat energy absorbed by an object, we can use the formula:

Q = mcΔT

where Q is the heat energy absorbed, m is the mass of the object, c is the specific heat capacity of the object, and ΔT is the change in temperature of the object.

Let's put in the given values:

m = 18 g (mass of object)

c = 0.900 J/(g*C) (specific heat of object)

ΔT = 40°C - 18°C = 22°C (change in temperature of object)

Now we can calculate the heat energy absorbed:

Q = mcΔT

Q = (18 g)(0.900 J/(g*C))(22°C)

Q = 356.4 J

Therefore, the object absorbed 356.4 J of heat energy.

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The pH of the buffered solution is 4.374.

A buffered solution is a solution that resists changes in pH when small amounts of acid or base are added to it.

In order to calculate the pH of a buffered solution, we need to use the Henderson-Hasselbalch equation, which is pH = pKa + log([A-]/[HA]). In this equation, pKa is the dissociation constant of the weak acid (benzoic acid in this case), [A-] is the concentration of the conjugate base (sodium benzoate), and [HA] is the concentration of the weak acid.

First, we need to find the concentrations of benzoic acid and sodium benzoate in the solution. We can use the equation n = cV, where n is the number of moles, c is the concentration, and V is the volume.

For benzoic acid:
n = (21.5 g / 122.12 g/mol) = 0.176 mol
c = 0.176 mol / 0.2 L = 0.88 M
[HA] = 0.88 M

For sodium benzoate:
n = (37.7 g / 144.11 g/mol) = 0.262 mol
c = 0.262 mol / 0.2 L = 1.31 M
[A-] = 1.31 M

Next, we need to find the pKa of benzoic acid. The pKa of benzoic acid is 4.20.

Now we can plug in the values into the Henderson-Hasselbalch equation:
pH = 4.20 + log([1.31]/[0.88])
pH = 4.20 + log(1.49)
pH = 4.20 + 0.174
pH = 4.374

Therefore, the pH of the buffered solution is 4.374.

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