if 75.0 g of water at 30.0°c absorbs 900 calories, the new temperature will be

It is significant to remember that the order of a reaction affects how a reaction's half-life is calculated. It is commonly expressed in seconds and is represented by the sign "t 1/2." The amount which is left after 172.8 years is 0.8 g.

The time it takes for the concentration of a particular reactant to reach 50% of its initial concentration, or the time it takes for the reactant concentration to reach half of its initial value, is known as the half-life of a chemical reaction.

To calculate the remaining amount:

N₀ / N = 2ⁿ

n = time / t1/2

172.8 / 57.6 = 3

N = 2ⁿ / N₀

N = 2³ / 10 = 0.8 g

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One would expect to find the densest ocean water at the bottom of the ocean, where the water is coldest and under the greatest pressure.

Ocean water is densest at the bottom, where it is coldest and under the greatest pressure. The salt content of seawater does affect its density, but it is not the primary factor. The density of seawater is determined by its temperature and salinity.

As seawater evaporates, the concentration of salt increases, but the volume of water decreases, leading to an increase in density. However, this effect is relatively small compared to the influence of temperature. Colder water is denser than warmer water, which means that the deep ocean is much denser than the surface.

Therefore, The density of seawater at the bottom of the ocean can reach up to 1,040 kilograms per cubic meter, which is almost 5% denser than surface seawater.

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The balanced equation for the reaction between sulfur (S₈) and oxygen (O₂) to form sulfur trioxide (SO₃) is 2S₈ + 16O₂ → 16SO₃.

Balancing chemical equations involves the addition of stoichiometric coefficients to the reactants and products.

The balanced equation for the reaction between sulfur (S₈) and oxygen (O₂) to form sulfur trioxide (SO₃) is determined as;

2S₈ + 16O₂ → 16SO₃

From the reactants side we can see that sulfur is 16 and also 16 in the product side. The number of oxygen in the reactant side is 32 and also 32 in the product side.

Thus, the balanced equation for the reaction between sulfur (S₈) and oxygen (O₂) to form sulfur trioxide (SO₃) is 2S₈ + 16O₂ → 16SO₃.

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Answer:

A

Explanation:

If Hydrogen is H₂  There will be two silver

and is Carbon is C There will only be one gray

and if Oxygen is O₃ There will be three red

The quantity of protons, neutrons, and electrons that each element has makes it unique.

Each chemical element's atoms has the same number of protons and electrons, which is important because neutrons' quantities are variable.

Isotopes are atoms with the same number of protons but differing numbers of neutrons.

They differ in mass, which affects their physical characteristics even if they have nearly identical chemical properties. There are unstable isotopes that emit radiation as well as stable isotopes that do not. These are referred to as radioisotopes.

Thus, The quantity of protons, neutrons, and electrons that each element has makes it unique.

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The synthesis of N-methyl-4-(p-tolyldiazenyl)aniline can be accomplished in a few steps, as outlined below:

Step 1: Nitration of toluene

Step 2: Reduction of p-nitrotoluene

Step 3: Diazotization of p-toluidine

Step 4: Coupling with N-methylaniline

Toluene is first nitrated to form p-nitrotoluene. This can be done by treating toluene with a mixture of nitric acid and sulfuric acid under controlled conditions. The reaction can be represented as follows:

Toluene + HNO3 → p-nitrotoluene + H2O

The p-nitrotoluene is then reduced to form p-toluidine, using a reducing agent such as iron and hydrochloric acid. The reaction can be represented as follows:

p-nitrotoluene + 6HCl + Fe → p-toluidine + 3H2O + FeCl3

The p-toluidine is then diazotized using nitrous acid to form the diazonium salt. The reaction can be represented as follows:

p-toluidine + HNO2 → p-tolyldiazonium chloride + H2O

The diazonium salt is then coupled with N-methylaniline to form N-methyl-4-(p-tolyldiazenyl)aniline. The reaction can be represented as follows:

p-tolyldiazonium chloride + N-methylaniline → N-methyl-4-(p-tolyldiazenyl)aniline + HCl

Overall reaction:

Toluene + HNO3 → p-nitrotoluene + H2O

p-nitrotoluene + 6HCl + Fe → p-toluidine + 3H2O + FeCl3

p-toluidine + HNO2 → p-tolyldiazonium chloride + H2O

p-tolyldiazonium chloride + N-methylaniline → N-methyl-4-(p-tolyldiazenyl)aniline + HCl

It is important to note that these reactions require careful handling and should only be attempted by individuals with proper training and experience in organic chemistry.

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The chemical elements involved are; hydrogen, fluorine, boron and lithium

There are two hydrogen atoms, five fluorine atoms, one boron atom and one lithium atom.

Chemical compounds are represented symbolically by chemical formulas, which reveal the types and amounts of atoms that make up the compound. It is a succinct approach to explain a substance's makeup.

The components of a compound are identified in a chemical formula by their corresponding chemical symbols, which are typically derived from their English or Latin names. The number of atoms of each element in a single compound molecule is indicated by the subscripts that follow each element.

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Based on the information regarding the titration, as the pH of the solution decreases, phenolphthalein will change color to pink.

The best indicator to use for a titration where you start out with a basic solution of around 8.0 and you expect to keep adding an acid until the mixture has a pH of 3.0 is phenolphthalein.

Phenolphthalein is an indicator that changes color in the pH range of 8.3 to 10.0. In basic solutions, phenolphthalein is colorless. As the pH of the solution decreases, phenolphthalein will change color to pink. The color change will be observed at the equivalence point of the titration, which is the point at which the amount of acid added is equal to the amount of base present. At the equivalence point, the pH of the solution will be 7.0.

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The difference between q for the two-step process and q for the one-step process is 220.38 joules.

To solve this problem, we use the first law of thermodynamics, which states that change in internal energy (ΔU) of system will be equal to the heat (q) added or removed from the system, minus the work (w) done by or on the system;

[tex]Δ_{U}[/tex] = q - w

For an ideal gas, the internal energy depends only on the temperature, so [tex]Δ_{U}[/tex] is zero if the final temperature is the same for both processes. Therefore, we can set [tex]Δ_{U}[/tex] to zero and solve for the difference in heat (q) between the two processes;

q(two-step) - q(one-step) = w(two-step) - w(one-step)

The work done by or on the gas can be calculated using the equation;

w = -P[tex]Δ_{V}[/tex]

where P is the external pressure, and [tex]Δ_{U}[/tex] is the change in volume. The negative sign indicates that work is done on the gas when it is compressed ([tex]Δ_{U}[/tex] < 0), and work is done by the gas when it expands ([tex]Δ_{U}[/tex] > 0).

For the two-step process, we can calculate the work done in two stages;

w(two-step) = -2.00 atm × (4.40 L - 2.20 L) - 2.50 atm × (2.20 L - 1.76 L)

= -3.32 atm L - 0.605 atm L

= -3.925 atm L

For the one-step process, we can calculate the work done in one step;

w(one-step) = -2.50 atm × (4.40 L - 1.76 L)

= -6.10 atm L

Substituting these values into the equation for the difference in heat, we get;

q(two-step) - q(one-step) = -3.925 atm L - (-6.10 atm L)

= 2.175 atm L

To convert this to joules, we need to multiply by the conversion factor for atm L to joules;

1 atm L = 101.3 J

Therefore; q(two-step) - q(one-step) = 2.175 atm L × 101.3 J/atm L

= 220.38 J

Therefore, the difference in heat between the two processes is 220.38 joules.

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After the minimum point, the conductance typically increases again as the concentration of ions in the solution increases.

Without additional context, it is difficult to determine what exactly is being referred to by "this minimum point." However, in general, the conductance of an electrolyte solution depends on the concentration of ions in the solution. Before the minimum point, the conductance typically increases as the concentration of ions in the solution increases. This is because more ions are available to carry the electric current through the solution, leading to a higher conductance. At the minimum point, the conductance reaches a minimum value due to a balance between the effect of ion concentration and the effect of ion mobility. At this point, the concentration of ions in the solution is not high enough to support a high conductance, while the mobility of the ions is not low enough to reduce the conductance significantly. The ion concentration rises to a level where it can support a larger conductance than at the minimum point, which causes this increase in conductance to occur. The addition or removal of a solute, the reaction between various species in the solution, or any number of other events can cause the concentration of ions in the solution to change throughout the process of changing ion concentrations. The amount of accessible ions in the solution is affected by the change in concentration, and this in turn influences the conductance of the solution. In conclusion, the concentration of ions in an electrolyte solution affects the conductance of the solution. The conductance rises with increasing ion concentration, falls to a minimal value at a specific point, and then rises once more with increasing ion  concentration continues to increase. The ion concentration in the solution can change due to various factors, which can affect the conductance of the solution.

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The amount of heat absorbed by 400 grams of water from 20°C to 99°C is 132,214.4 J.

The amount of heat absorbed or released by a substance can be calculated using the following equation;

Q = mc∆T

Where;

According to this question, 400.0 grams of water is heated in a pot on the stove from 20ºC to 99°C. The amount of heat absorbed can be calculated as follows:

Q = 400 × 4.184 × {99 - 20}

Q = 132,214.4 J

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27 grams of water are produced from the given amounts of hydrogen and oxygen.

To determine the amount of water produced from the reaction between hydrogen and oxygen, we need to compare the amounts of reactants (hydrogen and oxygen) to the stoichiometry of the balanced chemical equation.

The balanced equation is:

2H₂ + O₂ → 2H₂O

The molar mass of hydrogen (H₂) is 2 g/mol, and the molar mass of oxygen (O₂) is 32 g/mol.

Given:

Mass of hydrogen = 3 grams

Mass of oxygen = 24 grams

We can calculate the number of moles of each reactant by dividing their respective masses by their molar masses:

Number of moles of hydrogen = 3 grams / 2 g/mol = 1.5 moles

Number of moles of oxygen = 24 grams / 32 g/mol = 0.75 moles

According to the balanced equation, the ratio of hydrogen to water is 2:2, and the ratio of oxygen to water is 1:2. Therefore, the limiting reactant in this reaction is oxygen, as it is consumed in a smaller quantity compared to the stoichiometry of the reaction.

From the reaction, we can see that 1 mole of oxygen produces 2 moles of water. Thus, the number of moles of water produced is twice the number of moles of oxygen:

Number of moles of water = 2 * 0.75 moles = 1.5 moles

To determine the amount of water produced in grams, we multiply the number of moles by the molar mass of water (H₂O), which is approximately 18 g/mol:

Mass of water produced = 1.5 moles * 18 g/mol = 27 grams

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The change in temperature (ΔT) when a 25 g block of aluminum absorbs 10,000 J of heat is approximately 44.32°C.

To calculate the change in temperature (T) that occurs when an aluminium block absorbs a certain quantity of heat, we must utilise the specific heat capacity of aluminium (c) and the equation:

Q = mcΔT

Where Q is the heat absorbed or released, m is the substance's mass, c is the substance's specific heat capacity, and T is the temperature change.

The specific heat capacity of aluminium is approximately 0.897 J/g°C.

Given that the aluminium block weighs 25 g and absorbs 10,000 J of heat, we can plug the following values into the equation:

(25 g) * (0.897 J/g°C) * T = 10,000 J

We can now solve for T:

T = 10,000 joules / [(25 g) * (0.897 J/g°C)]

ΔT ≈ 44.32°C

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The heat capacity of a system is defined as the amount of heat required to raise the temperature through 1°C. It is denoted by c. It is an extensive property. The mass of steel bar is 47.93 g.

Here the amount of heat taken by the steel rod is equal to the amount of heat lost by water. The heat required to raise the temperature of the sample of mass 'm' having specific heat 'c' is:

Q = c (T - T₀) m

Cs (Ts - T0s) ms = -Cw (Tw - T0w) mw

ms = - Cw (Tw - T0w) mw / Cs (Ts - T0s)

Mass of water = 110 mL × 1.00 g / mL = 110.00 g

ms = -4.18 J / g°C × (21 .10 - 22.00) 110.00 g / 0.452 J / g°C (21.10 - 2.00) = 47.93 g

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The vibrational modes and unique possible states for each mode are detailed in the table below.

A vibrational mode of a molecule refers to a specific way in which the atoms inside a molecule can move relative to each other. Molecules are made up of atoms that are connected to each other by chemical bonds, and these bonds act like springs that can vibrate.

When a molecule absorbs energy, it can cause the bonds to stretch, bend, or twist in specific ways, creating different vibrational modes. The vibrational modes of a molecule can provide important information about its structure and chemical properties.

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The reactions that result in the emission of light involve the ruthenium label and tripropylamine (TPA), two electrochemically active molecules.

Thus, The electrode surface inside the measurement cell is where the reactions take place.

The ruthenium label is oxidized at the electrode surface as an electrical potential is applied, and TPA is oxidized into a radical cation that spontaneously loses a proton.

When the resultant TPA radical interacts with oxidized ruthenium, the ruthenium label enters an excited state and emits a photon (620 nm) before decaying. The ruthenium label is renewed and ready to carry out numerous light-generating cycles as it goes back to its ground state.

Thus, The reactions that result in the emission of light involve the ruthenium label and tripropylamine (TPA), two electrochemically active molecules.

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1. Using your knowledge of the Brønsted-Lowry theory of acids and bases, complete the following acid-base reactions and indicate each conjugate acid-base pair.

i. OH + HPO₂ → H₂O + H₂PO₄²⁻

The conjugate acid-base pair is OH/H₂O, HPO₂²⁻/H₂PO₄²⁻

2) Identify the conjugate acid-base pairs in the following reactions. Write A, B, CA, and CB below the appropriate substance.

i. HCO₃⁻ + NH₃ → NH₄⁺ + CO₃²⁻

The conjugate acid-base pair is HCO₃⁻/CO₃²⁻, NH₃/NH₄⁺

ii. HCI + H₂O → H₃O⁺ + Cl⁻

The conjugate acid-base pair is H₂O/OH⁻, HCI/Cl⁻, H₃O⁺/H₂O, Cl⁻/HCI

iii. CH₃COOH + H₂O → H₃O⁺ + CH₃COO⁻

The conjugate acid-base pair is CH₃COOH/CH₃COO⁻, H₂O/OH⁻, H₃O⁺/H₂O

iv. HOCI + NH₃ → NH₄⁺ + ClO⁻

The conjugate acid-base pair is HOCI/ClO⁻, NH₃/NH₄⁺

3. Write the formula for conjugate bases formed by the following acids.

i. HPO₄²⁻ → PO₄³⁻

ii. H₂O → OH⁻

iii. CN⁻ → HCN

iv. HOOC-COO⁻ → HOOCCOOH

4) Write the formula for conjugate acids formed by each of the following bases.

i. H₃O⁺ → H₂O

ii. HCN → H₂CN⁺

iii. NH₃ → NH₄⁺

5. Classify each of the following pH values as acidic, basic, or neutral.

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Answer:

Explanation:

The matching of each decimal number to the correct scientific notation is as follows:

3.07 x 10^-6 -> D) 3.07 x 10^-6

3.07 x 10^6 -> B) 3.07 x 10^6

3.07 x 10^-4 -> A) 3.07 x 10^-4

3.07 x 10^4 -> C) 3.07 x 10^4

So, the correct matching is:

D) 3.07 x 10^-6

B) 3.07 x 10^6

A) 3.07 x 10^-4

C) 3.07 x 10^4

Here is the balanced chemical equation for the reaction involving [tex][Cu(OH_2)_6]^{2+}:[/tex]

[tex][Cu(OH_2)_6]^{2+} + 4Cl^- = [CuCl_4]^{2-} + 6H_2O[/tex]

In this reaction, [tex][Cu(OH_2)_6]^{2+}[/tex] is a complex ion of copper(II) that reacts with chloride ions to form the complex ion [tex][CuCl_4]^{2-}[/tex] and water molecules.

The balanced equation indicates that for every one mole of [tex][Cu(OH_2)_6]^{2+[/tex] that reacts, four moles of chloride ions are required and two moles of [tex][CuCl_4]^{2-[/tex] and six moles of water are produced.

A balanced chemical equation is a written representation of a chemical reaction that shows the same number of atoms of each element on both the reactant and product sides of the equation.

In other words, the law of conservation of mass is obeyed in a balanced chemical equation, which states that the total mass of the reactants must equal the total mass of the products.

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The coordinate of the other x-intercept of a parabola with axis of symmetry x = -2 and crossing the x-axis at (-5,0) is (-1,0).

We know the vertex of the parabola in the example above is at the location (-2, y), where y is an integer. This is because the vertical line that passes through the vertex of a parabola is its axis of symmetry.

Since the parabola intersects the x-axis at (-5,0), we can infer that this location is a parabola's root. Given that the parabola is symmetric, a second root that is located at the same distance from the axis of symmetry must also exist.

The other root must be 3 units to the right of the axis of symmetry because the distance between the axis of symmetry and (-5,0) is 3 units to the left. The opposite x-intercept is therefore at (1, 0) or (-2 + 3, 0).

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The half-life of the radioactive isotope is 8 days.

Mass at 8 days = 8000 g

Number of half-lives in 4000 g = 8000 / 4000 = 2 half life

Time needed for 1000g to remain is 32 days.

The half life of a chemical reaction is the time required by the substance to reach half of its concentration. It is a characteristic property of the  unstable atomic nuclei and the way in which they decay.

For a given reaction the half life of a reactant is the time required for its concentration to reach a value that is the arithmetic mean of its initial and final value. For a reactant that is entirely consumed it is the time taken for the reactant concentration to fall to one half of its initial value.

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The maximum mass of carbon dioxide that could be produced by the chemical reaction is 46.2 g

First, we shall determine the limiting reactant. This obtained as follow

2CH₃(CH₂)₂CH₃ + 13O₂ -> 8CO₂ + 10H₂O

From the balanced equation above,

116 g of CH₃(CH₂)₂CH₃ reacted with 416 g of O₂

Therefore,

48 g of CH₃(CH₂)₂CH₃ will react with = (48 × 416) / 116 = 172.14 g of O₂

From the above calculation, we can see that a higher amount (i.e 172.14 g) of O₂ than what was given (i.e 54.6 g) is needed to react with 48 g of CH₃(CH₂)₂CH₃

Thus, the limiting reactant is O₂

Finally, we shall determine maximum mass of carbon dioxide, CO₂ produced. Details below:

2CH₃(CH₂)₂CH₃ + 13O₂ -> 8CO₂ + 10H₂O

From the balanced equation above,

416 g of O₂ reacted to produce 352 g of CO₂

Therefore,

54.6 g of O₂ will react to produce = (54.6 × 352) / 416 = 46.2 g of CO₂

Thus, the maximum mass of carbon dioxide, CO₂ produced is 46.2 g

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The energy associated with the formation of 2.55 g of 4He by the fusion of 3H and 1H is approximately -[tex]2.57 * 10^{-12 }.[/tex] Joules

The balanced nuclear equation for the fusion of 3H and 1H to form 4He is shown below:

3H + 1H → 4He

We find that the difference in mass between the reactants and products is: (3 × 3.01605 u) + (1 × 1.00783 u) - (1 × 4.00260 u) = -0.01854 u

Einstein's energy equation is E = mc².

E = (-0.01854 u) × (1.66054 × 10^-27 kg/u) × (2.998 × 10^8 m/s)^2

E = [tex]-4.03 * 10^{-12}[/tex] J

The number of reactions  =  2.55 g / 4.00260 g/mol = 0.637 mol

The total energy is =  [tex]-4.03 * {10^-12} J[/tex]× 0.637 mol

total energy = [tex]2.57 * 10^{-12} J[/tex]

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The gas would occupy approximately 3.00 L at 24.0 °C and 670 torr.

To solve this problem, we can use the combined gas law, which relates the pressure, volume, and temperature of a gas at different conditions. The combined gas law is expressed as:

(P1 × V1) / (T1) = (P2 × V2) / (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.

Using the given values, we can plug them into the equation and solve for V2:

(P1 × V1) / (T1) = (P2 × V2) / (T2)

(934 torr × 4.76 L) / (279.25 K) = (670 torr × V2) / (297.15 K)

Simplifying and solving for V2, we get:

V2 = [(934 torr × 4.76 L) / (279.25 K)] × (297.15 K / 670 torr)

V2 ≈ 3.00 L

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The pH of the 0.15 M [tex]CH_3COOH[/tex] solution is approximately 2.38. and around 2.9% of the [tex]CH_3COOH[/tex] molecules in the 0.15 M solution are deprotonated.

Acetic acid ([tex]CH_3COOH[/tex]) is a weak acid that only partially dissociates in water to form [tex]H^+[/tex] ions and [tex]CH_3COO^-[/tex] ions. To estimate the pH and fraction of [tex]CH_3COOH[/tex]molecules deprotonated in a 0.15 M [tex]CH_3COOH[/tex]solution, we can use the following equations and approximations:

The dissociation constant for acetic acid (Ka) is 1.8 x 10^-5.

The initial concentration of [tex]CH_3COOH[/tex] is equal to its concentration at equilibrium, since it only partially dissociates.

The concentration of [tex]H^+[/tex] ions is equal to the concentration of [tex]CH_3COO^-[/tex] ions at equilibrium, since the dissociation reaction involves a 1:1 ratio of [tex]H^+[/tex] ions to [tex]CH_3COO^-[/tex] ions.

Using these approximations, we can set up an equilibrium expression for the dissociation of [tex]CH_3COOH[/tex] :

[tex]Ka = [H^+][CH_3COO^-]/[CH_3COOH][/tex]

We also know that the initial concentration of [tex]CH_3COOH[/tex] is 0.15 M. Let x be the concentration of [tex]H^+[/tex] ions and [tex]CH_3COO^-[/tex] ions at equilibrium. Then:

[[tex]H^+[/tex]] = x

[[tex]CH_3COO^-[/tex]] = x

[[tex]CH_3COOH[/tex]] = 0.15 - x

Substituting these values into the equilibrium expression and solving for x, we get:

Ka = x^2 / (0.15 - x)

1.8 x 10^-5 = x^2 / (0.15 - x)

x = 0.0042 M

The pH can be calculated using the formula:

pH = -log[[tex]H^+[/tex]]

pH = -log(0.0042)

pH = 2.38

Therefore, the pH of the 0.15 M [tex]CH_3COOH[/tex] solution is approximately 2.38.

To estimate the fraction of [tex]CH_3COOH[/tex] molecules that are deprotonated, we can use the equation:

Fraction deprotonated = [tex][CH_3COO^-] / [CH_3COOH][/tex] x 100%

At equilibrium, the concentration of [tex]CH_3COO^-[/tex] ions is equal to the concentration of [tex]H^+[/tex] ions, which we calculated to be 0.0042 M. The concentration of [tex]CH_3COOH[/tex] at equilibrium is 0.15 - 0.0042 = 0.1458 M. Substituting these values into the equation, we get:

Fraction deprotonated = 0.0042 / 0.1458 x 100%

Fraction deprotonated = 2.9%

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The north pole of one magnet is near the South pole of the other magnet.

The ends of a magnet are called its poles. One end is called the north pole, the other is called the south pole. If you line up two magnets so that the south pole of one faces the north pole of the other, the magnets will pull toward each other.