Please solve whichever you can PICTURE INCLUDED! show work pls

The mass of BaSO₄ formed during the reaction is calculated as 4.67 g.

Equation that has equal number of atoms of each element on both the sides of equation is known as balanced chemical equation.

Balanced chemical equation for the reaction is: BaCl₂(aq) + Na₂SO₄ (aq) → BaSO₄(s) + 2NaCl(aq)

From the equation, we can see that 1 mole of BaCl₂ reacts with 1 mole of BaSO₄.

Given that 0.020 mol BaCl₂ reacts. Therefore, 0.020 mol BaSO₄ is formed.

To determine the mass of BaSO₄ formed, we can use the following formula: mass = moles x molar mass

So, mass = 0.020 mol x 233.39 g/mol

mass = 4.67 g

Therefore, the mass of BaSO4 formed during the reaction is 4.67 g.

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The percent yield of aspirin in this reaction is 71.1%.

What is Percentage Yield?

Percentage yield is a measure of the efficiency of a chemical reaction, expressed as a percentage. It is calculated by dividing the actual yield of the desired product by the theoretical yield (the maximum amount of product that can be produced from the given amounts of reactants) and multiplying the result by 100%.

The balanced chemical equation for the reaction is:

C7H6O3 + C4H6O3 → C9H8O4 + C2H4O2

The molar mass of salicylic acid is 138.12 g/mol and the molar mass of aspirin is 180.16 g/mol.

First, we need to calculate the theoretical yield of aspirin:

1 mol salicylic acid = 1 mol aspirin

0.1090 g salicylic acid * (1 mol / 138.12 g) * (1 mol / 1 mol) * (180.16 g / 1 mol) = 0.1405 g aspirin (theoretical yield)

The percent yield is calculated by dividing the actual yield by the theoretical yield and multiplying by 100:

Percent yield = (actual yield / theoretical yield) x 100

Percent yield = (0.1000 g / 0.1405 g) x 100

Percent yield = 71.1%

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There are 230.6 grams in 3.946 moles of NaCl.

The molar mass of a substance is the mass in grams of one mole of that substance.

To determine the number of grams in a given number of moles of a substance, you need to know its molar mass.

The molar mass of NaCl is the sum of the atomic masses of sodium (Na) and chlorine (Cl) in the compound, which are 22.99 g/mol and 35.45 g/mol, respectively. Therefore, the molar mass of NaCl is:

molar mass of NaCl = (1 x atomic mass of Na) + (1 x atomic mass of Cl)

molar mass of NaCl = (1 x 22.99 g/mol) + (1 x 35.45 g/mol)

molar mass of NaCl = 58.44 g/mol

To convert moles of NaCl to grams, you can use the following formula:

mass (in grams) = number of moles x molar mass

So, for 3.946 moles of NaCl:

mass = 3.946 moles x 58.44 g/mol

mass = 230.6 g

Therefore, the number of grams are 230.6.

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Since HCl is a strong acid, it completely dissociates in water. Therefore, the concentration of H⁺ in the solution is equal to the initial concentration of HCl, [H⁺] = 0.250 mol/L. Therefore, the pH of the solution can be:

pH = -log(0.250) = 0.602. Therefore, the pH of the solution resulting from the mixture of HCl and NH₂ is approximately 0.602, which is closest to option (A) 5.079.

pH is a measurement of the acidity or basicity of a solution. It is the negative logarithm of the concentration of hydrogen ions in the solution. A pH value of 7 is considered neutral, while values below 7 are acidic, and above 7 are basic.

Metals are not acidic or alkaline, as acidity and alkalinity are properties of solutions rather than the metals themselves. However, when metals react with acidic or alkaline solutions, they can produce ions that can affect the pH of the solution.

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The length of the side BC in the right triangle is 3.76 units.

We want to find the length of the side BC, for the right triangle ABC.

We know that:

ACB = 90°

ABC = 20°

AC = 4 units.

Now we need to use trigonometric relations to find BC, we can use the relation:

cos(a) = adjacent cathetus/hypotenuse

Replacing what we know we will get:

cos(20°) =BC/4

4*cos(20°) = BC = 3.76

That is the length.

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Answer:

The conjugate acid of a Bronsted-Lowry base is the species formed when it accepts a proton (H+).

C7H5O2- is a base because it can accept a proton to form its conjugate acid. To find the conjugate acid of C7H5O2-, we add a proton to it. The proton will bond with one of the oxygen atoms, and the resulting species will be:

C7H5O2H

Therefore, the conjugate acid of C7H5O2- is C7H5O2H.

Decomposers are organisms that convert dead plants or animals into the nutrients needed by living vegetation.

The energy-transfer capacity of an environment depends on decomposers. They break down decaying organisms into simpler inorganic materials, releasing nutrients that can be used by main producers.

Decomposers are a class of organisms that make up the last component in the food chain. They decompose dead vegetation and animals and replenish the soil's essential nutrients. Because they are the original source of energy that is passed between other organisms, primary producers are crucial to the entire food chain.

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Answer:

Explanation:

This simulation demonstrates the law of universal gravitation by showing how the gravitational force between objects depends on their masses and the distance between them.

The new planet is located in the habitable zone and has a similar atmosphere to Earth, with oxygen and nitrogen. It also has a magnetic field that protects it from solar winds and a stable climate that supports a diverse range of ecosystems.

If the masses of the planets were different, it would affect the results because the gravitational force between the planets would change.

The sun's mass affects planets in a solar system by influencing the pace of the planets' orbit around it.

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If Bill used 6M HCl instead of 6M H2SO4, he would observe a different chemical reaction or no reaction at all, depending on the experiment and the reaction conditions.

HCl (hydrochloric acid) is a strong acid, while H2SO4 (sulfuric acid) is a stronger acid. They have different chemical properties and react differently with other substances. Therefore, using HCl instead of H2SO4 may result in different reaction or no reaction at all, depending on experiment and reaction conditions.

For example, if Bill was trying to dissolve a metal in the acid to produce hydrogen gas, then reaction with HCl may be slower or not happen at all, depending on the type of metal, while the reaction with H2SO4 would be more vigorous. On the other hand, if Bill was trying to neutralize a basic solution with acid, then reaction with HCl would still result in the formation of salt and water, although the amount of acid required to achieve same level of neutralization may be different.

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it would take approximately 1.986 ×

[tex] {10}^{25} [/tex]

photons to heat 205 mL of coffee from 25.0 °C to 62.0 °C using microwave radiation with a wavelength of 12.4 cm.

The first step is to calculate the amount of energy required to heat the coffee. We can use the formula:

Q = mcΔT

where Q is the amount of energy required, m is the mass of the coffee, c is the specific heat capacity, and ΔT is the change in temperature.

The mass of the coffee can be calculated as:

m = density × volume

m = 0.997 g/mL × 205 mL = 204.485 g

ΔT = 62.0 °C - 25.0 °C = 37.0 °C

Q = (204.485 g) × (4.184 J/(g⋅K)) × (37.0 °C) = 31612.09 J

The next step is to calculate the energy per photon of the microwave radiation. We can use the formula:

E = hc/λ

where E is the energy per photon, h is Planck's constant, c is the speed of light, and λ is the wavelength of the radiation.

Converting the wavelength to meters:

λ = 12.4 cm = 0.124 m

[tex]E = (6.626 × 10^-34 J⋅s) × (2.998 × 10^8 m/s) / (0.124 m) = 1.594 × 10^-22 J/photon[/tex]

Finally, we can calculate the number of photons required by dividing the energy required to heat the coffee by the energy per photon of the microwave radiation:

Number of photons = Q / E

photon =

[tex]1.986 × {10}^{25} photons[/tex]

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Answer: Each oxygen atom has 8 protons in its nucleus, while each nitrogen atom has only 7 protons in its nucleus. Thus, the overall size of the electron cloud of the O2 molecule is smaller than for N2, in part because its electron cloud is drawn in closer to the O nuclei by the greater positive charge on the O nuclei.

Answer:

To calculate the initial concentration of HCl, we can use the following formula: M1V1 = M2V2 where M1 is the initial concentration of HCl, V1 is the volume of HCl used in the titration (10.0 mL), M2 is the concentration of NaOH (0.140 M), and V2 is the volume of NaOH used to reach the endpoint of the titration (13.5 mL). Rearranging the formula to solve for M1, we get: M1 = (M2V2) / V1 Substituting the given values, we get: M1 = (0.140 M)(13.5 mL) / 10.0 mL M1 = 0.189 M Therefore, the initial concentration of HCl is 0.189 M.

Answer:

C. Fluorine (F) is most likely to form a molecule with sodium that includes one ionic bond. Fluorine is a highly reactive nonmetal, and it tends to gain one electron to form a fluoride ion (F-). Sodium is a highly reactive metal that tends to lose one electron to form a sodium ion (Na+). When these two elements react, they form an ionic compound, sodium fluoride (NaF), which includes one ionic bond between Na+ and F-.

Explanation:

(i) The provided reaction's rate law is: r = k[A][B]. ² (ii) The units of k are influenced by the reaction's overall sequence. The general formula for the reaction is 1 + 2 = 3. As a result, k is measured in L²/mol².s.

The formula t1/2 = 0.693/k gives the first-order reaction's half-life (t1/2).

In light of this, k = 0.693/t1/2 = 0.693/140 s = 0.00495 [tex]t^{-1}[/tex].

For a first-order reaction, [AB]t = [AB]0 * e(-kt),

where [AB]0 is the initial concentration of AB, gives the quantity of AB that is left over at time t. [AB]t = 1.50 mol/L * e(-0.00495 [tex]s^{-1}[/tex]* 600 s)

= 0.606 mol/L when the specified values are substituted.

The formula k = 1/(t1/2*[AB]0) gives the rate constant (k) for a second-order reaction in terms of the half-life (t1/2). t1/2 = 1/(k*[AB]0) = 1/(0.055 L/mol.s * 1.50 mol/L) = 12.1 s, and this is the result.

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Answer:

the pressure of the gas is 1.67 atm when the volume increased to 4.5 L.

Explanation:

Assuming the temperature and the amount of gas remain constant (i.e., the process is isobaric):

Using Boyle's law, we can relate the initial pressure (P1) and volume (V1) to the final pressure (P2) and volume (V2):

P1V1 = P2V2

Plugging in the given values:

P1 = 1.50 atm

V1 = 5.00 L

V2 = 4.5 L

Solving for P2:

P2 = (P1V1)/V2 = (1.50 atm x 5.00 L)/4.5 L = 1.67 atm

Answer:

To solve this problem, we need to first write a balanced chemical equation for the reaction between carbon monoxide (CO) and iron (III) oxide (Fe2O3): 3CO + Fe2O3 -> 2Fe + 3CO2 From the equation, we can see that 3 moles of CO are required to react completely with 1 mole of Fe2O3. We can use this ratio to convert the mass of Fe2O3 to moles: 116 kg Fe2O3 * (1 mol Fe2O3/159.69 g Fe2O3) = 727.57 mol Fe2O3 So we need 3 times as many moles of CO: 727.57 mol Fe2O3 * (3 mol CO/1 mol Fe2O3) = 2182.7 mol CO Therefore,

the enthalpy of reaction for HCl(g) + NaNO₂(s) → HNO₂(l) + NaCl(s) 2NaCl(s) + H₂O(l) → 2HCl(g) + Na₂O(s) ∆H° = -507.1 kJ/mol NO(g) + NO₂(g) + Na₂O(s) → 2NaNO₂(s) ∆H° = -427.0 kJ/mol NO(g) + NO₂(g) → N₂O(g) + O₂(g) ∆H° = -43.01 kJ/mol 2HNO₂(l) → N₂O(g) + O₂(g) + H₂O(l) ∆H° = +34.02 kJ/mol the enthalpy of reaction for the given reaction is -39.1 kJ/mol.

We can use the given reactions and their enthalpies to find the enthalpy of reaction for the given equation.

The given equation is:

HCl(g) + NaNO₂(s) → HNO₂(l) + NaCl(s)

We can break down this reaction into several steps using the given reactions as follows:

Na₂O(s) + 2HCl(g) → 2NaCl(s) + H₂O(l) (reverse of the given reaction)

∆H° = +507.1 kJ/mol (reverse the sign of given reaction)

2NaCl(s) + H₂O(l) → Na₂O(s) + 2HCl(g)

∆H° = -507.1 kJ/mol (given reaction)

NO(g) + NO₂(g) + Na₂O(s) → 2NaNO₂(s)

∆H° = -427.0 kJ/mol (given reaction)

2HNO₂(l) → N₂O(g) + O₂(g) + H₂O(l)

∆H° = +34.02 kJ/mol (given reaction)

NO(g) + NO₂(g) → N₂O(g) + O₂(g)

∆H° = -43.01 kJ/mol (given reaction)

Now, we can add these equations and their enthalpies to get the overall enthalpy of the given reaction:

HCl(g) + NaNO₂(s) → HNO₂(l) + NaCl(s)

H₂O(l) + 2NaCl(s) → Na₂O(s) + 2HCl(g) ∆H° = -507.1 kJ/mol

Na₂O(s) + NO(g) + NO₂(g) → 2NaNO₂(s) ∆H° = -427.0 kJ/mol

2HNO₂(l) → N₂O(g) + O₂(g) + H₂O(l) ∆H° = +34.02 kJ/mol

NO(g) + NO₂(g) → N₂O(g) + O₂(g) ∆H° = -43.01 kJ/mol

HCl(g) + NaNO₂(s) → HNO₂(l) + NaCl(s) ∆H° = -39.1 kJ/mol

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Humans primarily form communities because social interaction is essential for our survival and well-being.

Living in communities provides us with numerous benefits that we cannot obtain on our own, including protection, food and resource sharing, cooperation, and support. Communities allow us to pool resources and skills, to share knowledge and experiences, and to work together to achieve common goals.

In addition, humans are social creatures by nature, and we have a natural inclination to form social connections and relationships with others. Being part of a community satisfies this need for social interaction and can lead to increased feelings of belonging, purpose, and happiness. Community also provides opportunities for personal growth, learning, and development, as we are exposed to different perspectives, ideas, and experiences through interactions with others.

Overall, forming communities allows humans to better navigate the challenges and opportunities of the world, and to achieve a higher quality of life through cooperation and collaboration.

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Baking powder is a mixture of sodium bicarbonate, other bicarbonates, and acid salts. Baking powder is a leavening agent produced by the mixture of an acid reacting with an alkali reacting one. These baking acids are tartrate, phosphate, and sodium aluminium sulphate, used alone or in combination.

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Answer:

2.25 x 10^-5 moles or 1.355 x 10^19 atoms

Explanation:

Menthol has the chemical formula C10H20O, which means that for every 1 mole of oxygen (O) in a sample of menthol, there are 10 moles of carbon. So if there are 2.25 x 10^-6 moles of oxygen in a sample of menthol, then there are 10 * 2.25 x 10^-6 = 2.25 x 10^-5 moles of carbon in the same sample.

Since there are Avogadro’s number (6.022 x 10^23) atoms in one mole of any substance, there are 2.25 x 10^-5 moles * 6.022 x 10^23 atoms/mole = 1.355 x 10^19 atoms of carbon in the same sample.

The reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) is exothermic reaction.

In exothermic reaction, energy is transferred into surroundings rather than taking energy from surroundings as in the endothermic reaction.

In this reaction, HCl reacts with NaOH to form water (H₂O) and sodium chloride (NaCl) while releasing energy in the form of heat. The reaction is as follows: HCl + NaOH → NaCl + H₂O + heat

This means that the reaction releases heat to the surroundings, and the temperature of the mixture increases. This is why this reaction is exothermic in nature.

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Answer:

the mass of C9H8O4 produced from 67.4 g of C7H6O3 is 94.19 g.

Explanation:

To solve this problem, we need to use stoichiometry and the given yield percentage. First, we need to write and balance the chemical equation for the reaction:

C7H6O3 (s) + C4H6O3 (s) → C9H8O4 (s) + HC2H3O2 (aq)

From the equation, we can see that one mole of C7H6O3 reacts with one mole of C4H6O3 to produce one mole of C9H8O4. Therefore, we can calculate the number of moles of C9H8O4 produced from 67.4 g of C7H6O3 as follows:

molar mass of C7H6O3 = 122.12 g/mol

moles of C7H6O3 = 67.4 g / 122.12 g/mol = 0.551 moles

Since the reaction has a 95.0% yield, the actual amount of C9H8O4 produced will be 95.0% of the theoretical yield. Therefore, we can calculate the theoretical yield of C9H8O4 as follows:

moles of C9H8O4 = moles of C7H6O3 = 0.551 moles

mass of C9H8O4 = moles of C9H8O4 × molar mass of C9H8O4

mass of C9H8O4 = 0.551 mol × 180.16 g/mol

mass of C9H8O4 = 99.15 g

Finally, we can calculate the actual yield of C9H8O4 as 95.0% of the theoretical yield:

actual yield of C9H8O4 = 95.0% × 99.15 g

actual yield of C9H8O4 = 94.19 g

The correct answer is C: 0.86, 2.68, 110. The Global Warming Potential (GWP) is a measure of how much a given mass of a greenhouse gas contributes to global warming, relative to the same mass of carbon dioxide (CO₂).

The GWP takes into account the radiative forcing of each greenhouse gas and its atmospheric lifetime.

For a time horizon of 20 years, the GWP values are:

Methane: 86

Nitrous oxide: 268

CFC-12: 11,000

These values indicate that, over a 20-year period, methane is 86 times more potent as a greenhouse gas than CO₂, nitrous oxide is 268 times more potent, and CFC-12 is 11,000 times more potent.

To convert the GWP values to CO₂ equivalents, we multiply each value by the GWP of CO₂ (which is defined as 1). Therefore, the CO₂ equivalents for methane, nitrous oxide, and CFC-12 are:

Methane: 0.86 CO₂ equivalents

Nitrous oxide: 2.68 CO₂ equivalents

CFC-12: 110 CO₂ equivalents

Therefore, the correct answer is C: 0.86, 2.68, 110, as it lists the CO₂ equivalents in order for methane, nitrous oxide, and CFC-12, respectively.

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Answer: invest more time in consistent practice

Explanation:

Answer:H-F>F-F>H-I>H-H

Explanation:The polarity of a bond is determined by the difference in electronegativity between the two atoms of the bond. Electronegativity is a measure of an atom's ability to attract electrons to it in a chemical bond. The greater the difference in electronegativity between two atoms, the more polar the bond.

The electronegativity values for the atoms:

H: 2.2

F: 3.98

I: 2.66

Based on the law of superposition, geologists can conclude that the limestone rock layer is younger than the sandstone layer below it.

This is because the law of superposition states that in an undisturbed sequence of rock layers, the oldest layer is at the bottom and the youngest layer is at the top. Therefore, since the sandstone layer is found below the limestone layer, it must be older.

The age of the limestone layer itself cannot be determined solely based on the law of superposition. While geologists can infer that the limestone layer is younger than the underlying sandstone layer, they would need to use other methods such as radiometric dating to determine the actual age of the rock layer.

Similarly, the presence of fossils in the limestone layer cannot be determined based solely on the law of superposition. While it is possible that the limestone layer may contain fossils, this would need to be confirmed through further investigation and analysis.

The age of another layer 100 kilometers away also cannot be determined solely based on the law of superposition. While the law of superposition can provide information about the relative ages of rock layers within a local area, it cannot be used to compare the ages of rock layers in different locations.

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Answer:

3.998 grams NaOH

Explanation:

Since Na2SO4 + 2CuSO4 = 2NaSO4 + Cu2SO4 has an equal number of each element in its reactants and products, the equation is balanced.

A chemical equation that is balanced has the same number of each type of atom on both sides of the equation. Subscripts are a component of the chemical formulas for the reactants and products that show how many atoms of the previous element there are in each.

Count the atoms on each side first. Next, alter one of the compounds' coefficients. Finally, count the atoms once more, and then repeat steps two and three until the equation is balanced.

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Answer:

To solve this problem, we first need to write the balanced chemical equation for the reaction between formic acid (HCOOH) and sodium hydroxide (NaOH): HCOOH + NaOH → NaCOOH + H2O From the equation, we can see that 1 mole of HCOOH reacts with 1 mole of NaOH to produce 1 mole of NaCOOH and 1 mole of H2O. Therefore, the number of moles of NaOH added can be calculated as follows: moles of NaOH = concentration × volume = 0.12 M × 0.075 L = 0.009 mol Since the reaction is a neutralization reaction, the number of moles of HCOOH initially present can be calculated as follows: moles of HCOOH = concentration × volume = 0.25 M ×

Answer:

4.88

Explanation:

Formic acid is a weak acid and its dissociation can be represented by the equation: HCOOH ⇌ H+ + HCOO-. The acid dissociation constant (Ka) for this reaction is 1.77*10^-4. When NaOH is added to the solution, it will react with the formic acid to produce its conjugate base (formate ion) and water. This reaction can be represented by the equation: HCOOH + OH- → HCOO- + H2O.

To calculate the resulting pH, we need to determine the number of moles of formic acid and NaOH present in the solution. The number of moles of formic acid can be calculated by multiplying its molarity by its volume in liters: 0.25 M * 0.055 L = 0.01375 moles. Similarly, the number of moles of NaOH can be calculated as: 0.12 M * 0.075 L = 0.009 moles.

Since NaOH is a strong base, it will react completely with formic acid to produce formate ions and water. This means that 0.009 moles of formic acid will react with 0.009 moles of NaOH to produce 0.009 moles of formate ions and water.

After the reaction, there will be 0.01375 - 0.009 = 0.00475 moles of formic acid left in the solution and 0.009 moles of formate ion produced.

The total volume of the solution after adding NaOH is 55 mL + 75 mL = 130 mL or 0.13 L.

We can now use an ICE table to calculate the equilibrium concentrations of all species present in the solution:

(ICE table Picture attached below)

Substituting these values into the expression for Ka and solving for x gives us:

Ka = [H+][HCOO-]/[HCOOH] = x(0.009/0.13 + x)/(0.00475/0.13 - x) = 1.77*10^-4

Solving this quadratic equation gives us x = [H+] = 1.33*10^-5 M.

The pH of the solution can now be calculated as pH = -log[H+] = -log(1.33*10^-5) = 4.88.

So, the resulting pH after adding NaOH to the formic acid solution is 4.88.

The final temperature of the water is 28.9°C for the given copper rod,  assuming no heat is lost to the container or the air.

Temperature, a measure of hotness or coldness expressed in terms of any of several arbitrary scales and showing the direction in which heat energy will naturally flow—that is, from a hotter (higher) body to a colder body. (one at a lower temperature). Temperature is not the equivalent of a thermodynamic system's energy; for example, a burning match is much hotter than an iceberg, but the total heat energy contained in an iceberg is much larger than the energy contained in a match. Temperature, like pressure or density, is referred to as an intensive property—one that is independent of the quantity of substance under consideration—as opposed to extensive properties such as mass or volume.

The final temperature of the water can be calculated using the equation Q = mcΔT,

where Q is the heat energy,

m is the mass of the sample,

c is the specific heat capacity of the sample,

and ΔT is the temperature difference between the sample and the water.

Q = (10.0 g) ×(0.383 J/g °C) ×(90°C -20°C)

 = 2647 J

The equation Q = mcΔT can be rearranged to ΔT = Q/mc.

Applying this to the given scenario:

ΔT = [tex]\frac{2647 J}{120mL}[/tex] × (4.18 J/g·°C)

 = 8.9°C

Therefore, the final temperature of the water would be 28.9°C.

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