Calculate the pH at 25°C of a 0.29M solution of ammonium bromide NH4Br . Note that ammonia NH3 is a weak base with a pKb of 4.75 . Round your answer to 1 decimal place.

In compound A, the best leaving group is the O –OH group, and the worst leaving group is the –OH group.

The correct ranking from best to worst leaving group is O –OH, > –NH, > –OH.

To explain this step-by-step:

1. A good leaving group is one that can easily dissociate from the molecule, stabilizing the negative charge it acquires upon leaving.
2. The O –OH group, being an alkoxide ion, is a better leaving group because it can stabilize the negative charge through resonance.
3. The –NH group is the next best leaving group, as it can somewhat stabilize the negative charge through its lone pair of electrons.
4. Finally, the –OH group is the worst leaving group among the given options, as it is less capable of stabilizing the negative charge upon leaving the molecule.

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A chemical bond refers to the linking of atoms together to form molecules. Some key characteristics of chemical bonds:

1. They hold atoms together in a molecule. Chemical bonds keep the atoms together rather than having them float apart.

2. They involve the sharing or transfer of electrons between atoms. The bonds are formed due to the electrostatic attraction between positive and negative charges. For example, in an ionic bond, electrons are transferred from one atom to another. In a covalent bond, electrons are shared between atoms.

3. They determine many of the properties of a compound. The strength, polarity, directionality of bonds have a strong influence on properties such as melting point, solubility, conductivity, etc.

4. They can be made and broken. Chemical bonds can form during chemical reactions and break apart during other reactions.

5. They involve the sharing or redistribution of orbital density between atoms. Electrons in atomic orbitals redistribute to form molecular orbitals that surround the nuclei.

6. They align atoms into geometric arrangements. Chemical bonds orient atoms in specific spatial configurations, which determines the molecular geometry and polarity.

7. They influence chemical reactivity. The strength and stability of chemical bonds determine whether a molecule will readily react with other compounds. Weaker bonds are more reactive.

That covers the basic highlights of a chemical bond. Let me know if you have any other questions!

The addition of hydrogen (H2/Pt) to alkenes takes place with syn stereospecificity, meaning that the two hydrogen atoms are added to the same side of the double bond. Therefore, the correct answer is d. Hydrogenation (H2/Pt).

The other reactions listed do not have stereospecificity:a. Addition of HBr results in the formation of both the syn and anti addition products, meaning that the H and Br can add to either the same side or opposite sides of the double bond.b. Acid-catalyzed hydration (H2O/H2SO4) also does not have stereospecificity because the water molecule can add to either side of the double bond, leading to the formation of both the syn and anti addition products.

c. Addition of bromine (Br2) also does not have stereospecificity, as the two Br atoms can add to either side of the double bond, leading to the formation of both the syn and anti addition products.

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a. The solubility of AgIO₃ in a 0.285 M solution of NaIO₃ is 1.06 x 10⁻⁸ M. b. The solubility of La(IO₃)₃ in a 0.285 M solution of NaIO₃ is 4.31 x 10⁻¹² M. c. AgIO₃ is more soluble than La(IO₃)₃.

a. To calculate the solubility of AgIO₃, we need to first write the balanced chemical equation for the dissolution of AgIO₃ in water: AgIO₃(s) ⇌ Ag⁺(aq) + IO₃⁻(aq). The Ksp expression for this reaction is: Ksp = [Ag⁺][IO₃⁻]. Let x be the solubility of AgIO₃ in a 0.285 M solution of NaIO₃. Then, the equilibrium concentrations of Ag⁺ and IO₃⁻ are both equal to x. The initial concentration of IO₃⁻ is 0.285 M. Substituting the values into the Ksp expression and solving for x gives: x² = Ksp/[IO₃⁻] = (3.0 x 10⁻⁸)/(0.285) = 1.06 x 10⁻⁸ M.

b. The balanced chemical equation for the dissolution of La(IO₃)₃ in water is: La(IO₃)₃(s) ⇌ La³⁺(aq) + 3IO₃⁻(aq). The Ksp expression for this reaction is: Ksp = [La³⁺][IO₃⁻]³. Let x be the solubility of La(IO₃)₃ in a 0.285 M solution of NaIO₃. Then, the equilibrium concentrations of La³⁺ and IO₃⁻ are both equal to x. The initial concentration of IO₃⁻ is 0.285 M. Substituting the values into the Ksp expression and solving for x gives: x⁴ = Ksp/[IO₃⁻]³ = (7.5 x 10⁻¹²)/(0.285)³ = 4.31 x 10⁻¹² M.

c. Since the solubility of AgIO₃ is greater than the solubility of La(IO₃)₃ in a 0.285 M solution of NaIO₃, AgIO₃ is more soluble than La(IO₃)₃.

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The volume of added base beyond which the pH is calculated by focusing on the amount of excess strong base added is referred to as the equivalence point.

At this point, the amount of added strong base is equal to the amount of acid in the solution. The pH at the equivalence point depends on the strength of the acid and base being titrated.

When a strong base is added to a weak acid, the pH of the solution increases gradually until it reaches the equivalence point. However, if a strong acid is added to a weak base, the pH decreases until it reaches the equivalence point.

In general, the pH changes rapidly near the equivalence point, so it is important to add the base slowly near the end of the titration to accurately determine the equivalence point. Once the equivalence point is reached, the pH is calculated based on the amount of excess strong base added. The pH at the equivalence point can be used to determine the concentration of the acid or base being titrated.

In conclusion, the volume of added base beyond which the pH is calculated by focusing on the amount of excess strong base added is the equivalence point. Accurately determining the equivalence point is crucial in determining the concentration of the acid or base being titrated.

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Tetrodotoxin blocks sodium channels, which prevents the influx of sodium ions and inhibits the generation and propagation of action potentials, leading to a loss of excitatory conduction in neurons.

Sodium channels are responsible for the rapid depolarization phase of the action potential in neurons. When an action potential is initiated, voltage-gated sodium channels open and allow an influx of sodium ions into the neuron, which depolarizes the membrane potential and triggers the propagation of the action potential down the axon.

Tetrodotoxin works by binding to the extracellular pore of the sodium channel and blocking the flow of sodium ions through the channel. This prevents the rapid depolarization of the membrane potential, which is necessary for the generation of action potentials. As a result, neurons are unable to generate action potentials and their ability to conduct electrical impulses is greatly diminished.

In summary, tetrodotoxin inhibits excitatory conduction in neurons by blocking sodium channels and preventing the generation and propagation of action potentials. This can lead to a range of neurological symptoms, including muscle weakness, paralysis, and respiratory failure, and can be fatal in high enough doses.

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The final molarity when adding 125 mL of water to 25.0 mL of a 3.0 M solution of KOH is 0.5 M

First, we shall list out the given parameters from the question. Details below:

The final molarity of KOH solution can be obtained by using the dilution formular as illustrated below:

M₁V₁ = M₂V₂

3 × 25 = M₂ × 150

75 = M₂ × 150

Divide both side by 150

M₂ = 75 / 150

M₂ = 0.5 M

Thus, we can conclude that the final molarity of KOH solution is 0.5 M

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The ways that the brightness of the flame can be increased are shown below.

By boosting the airflow into the burner, the flame's brilliance can be improved. Increasing the gas flow rate or changing the air intake valve can do this.

Using a gas that generates a brighter flame, like propane or butane, will increase the brightness of the flame. These gases produce a yellow flame because they have a higher carbon to hydrogen ratio than natural gas.

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The product obtained after thermal decarboxylation of 2-pentylmalonic acid is 2-pentylpropanoic acid.

2-pentylmalonic acid has the following structure:

HOOC-CH(COOR)-CH2-CH2-CH2-CH3

Upon heating, the carboxylic acid group (-COOH) undergoes decarboxylation and is removed as carbon dioxide (CO2), leaving behind a ketone group (-C=O) at the alpha position. The remaining molecule is then the corresponding alkyl acid.

Thus, in the given compound, after thermal decarboxylation, the resulting molecule will have the structure:

CH3-CH2-CH2-CH2-CO-CH2-CH2-CH3

which is 2-pentylpropanoic acid.

Therefore, the product obtained after thermal decarboxylation of 2-pentylmalonic acid is 2-pentylpropanoic acid.

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The stronger acid between H₂S₂O₃ (thiosulfuric acid) and H₂SO₄ (sulfuric acid) is H₂SO₄.

To determine the stronger acid, we can compare their acid dissociation constant (Ka) values. A higher Ka value indicates a stronger acid, as it shows a greater tendency to donate a proton (H⁺).

Sulfuric acid (H₂SO₄) has a higher Ka value, with its first dissociation constant being around 10¹, while thiosulfuric acid (H₂S₂O₃) has a much lower Ka value. Therefore, H₂SO₄ is the stronger acid.

Additionally, the strong acidity of H₂SO₄ can be attributed to the highly electronegative oxygen atoms present in its structure, which stabilizes the negatively charged conjugate base (HSO₄⁻) formed after donating a proton.

On the other hand, H₂S₂O₃ has sulfur atoms in its structure, which are less electronegative and less able to stabilize the negative charge on the conjugate base, making it a weaker acid.

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Complete question:

Choose the stronger acid in each of the following pairs:

H₂S₂O₃ or H₂SO₄

2 NH₄⁺(aq) + 3 Zn²⁺(aq) + 2 PO₄³⁻(aq) → Zn₃(PO₄)₂(s) + 6 NH₄⁺(aq) is the net ionic equation.

The balanced net ionic equation for the reaction when aqueous (NH₄)₃PO₄ and aqueous Zn(NO₃)₂ are mixed in solution to form solid Zn₃(PO₄)₂ and aqueous NH₄NO₃ is:

2 NH₄⁺(aq) + 3 Zn²⁺(aq) + 2 PO₄³⁻(aq) → Zn₃(PO₄)₂(s) + 6 NH₄⁺(aq)

The nitrate ions (NO₃⁻) do not participate in the reaction and are therefore not included in the net ionic equation. Additionally, the ammonium ions (NH₄⁺) are spectator ions and are therefore also not included in the net ionic equation.

Therefore, The phases for each species in the equation are:

NH₄⁺(aq) - ammonium ion, aqueous

Zn²⁺(aq) - zinc ion, aqueous

PO₄³⁻(aq) - phosphate ion, aqueous

Zn₃(PO₄)₂(s) - zinc phosphate, solid

NH₄⁺(aq) - ammonium ion, aqueous

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The concentration of OH- in a 0.724 M solution of BrO- is 4.0 x 10^-6 M.

To determine the concentration of OH- in a 0.724 M solution of BrO-, we first need to find the concentration of the corresponding BrO- ion. Since BrO- is a weak base, we can use the Kb value to calculate the concentration of OH- ions produced when it dissociates.

First, we need to write the balanced equation for the dissociation of BrO-:
BrO- + H2O ⇌ OH- + HBrO

The Kb expression for this reaction is:
Kb = [OH-][HBrO]/[BrO-]

Since we are given the Kb value and the concentration of BrO-, we can solve for [OH-]:
Kb = [OH-][HBrO]/[BrO-]
4.0 x 10^-6 = [OH-][0.724]/[BrO-]
[OH-] = (4.0 x 10^-6)(0.724)/[BrO-]

To solve for [BrO-], we need to use the fact that it dissociates according to the equation:
BrO- + H2O ⇌ OH- + HBrO

This means that the concentration of BrO- will be equal to the initial concentration of the solution, which is 0.724 M.

Plugging in the values, we get:
[OH-] = (4.0 x 10^-6)(0.724)/0.724
[OH-] = 4.0 x 10^-6 M

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The molarity of the Ca(OH)₂ solution from the balanced reaction above is 0.0846 M.

To calculate the molarity of the Ca(OH)₂ solution, we must convert the mass of KHP consumed (0.914 g) to moles. Use the molar mass of KHP (204.22 g/mol):

moles KHP = 0.914 g / 204.22 g/mol

= 0.00447 mol

Use the 1:2 mole ratio between Ca(OH)₂ and KHP:

moles Ca(OH)₂ = 0.00447 mol KHP / 2

= 0.002235 mol

Convert the volume of Ca(OH)₂ titrated (26.42 mL) to liters:

volume Ca(OH)₂ = 26.42 mL * (1 L / 1000 mL)

= 0.02642 L

Calculate the molarity of Ca(OH)₂ solution:

Molarity Ca(OH)₂ = moles Ca(OH)₂ / volume Ca(OH)₂

= 0.002235 mol / 0.02642 L

= 0.0846 M

Thus, the molarity of the Ca(OH)₂ solution is 0.0846 M.

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As scientific knowledge and technology advance, instrumentation also changes and evolves to better support scientific research and experimentation.

What is Science?

Science is a systematic and evidence-based approach to studying the natural world, including physical, biological, and social phenomena. It involves formulating hypotheses, conducting experiments, and analyzing data to generate knowledge and understanding about how the world works.

Advances in fields such as materials science, electronics, and computing have allowed for the development of more sophisticated and precise instruments, leading to new discoveries and greater understanding of the natural world.

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The element in period 3 with successive ionization energies (IE1 = 578, IE2 = 1820, IE3 = 2740, IE4 = 11,500, and IE5 = 13,000) is Magnesium (Mg).

The very minimum energy required to remove one electron from a gaseous atom in isolation is referred to as ionization energy. Because these atoms are more stable and have orbitals that are partially and completely occupied, it takes more energy to remove an electron from them. In the case of such atoms, the ionization enthalpy is thus larger than the expected value.

To identify the element in period 3 with the successive ionization energies (IEs) in kJ/mol (IE1 = 578, IE2 = 1820, IE3 = 2740, IE4 = 11,500, and IE5 = 13,000), we need to follow these steps:

1. Locate the period 3 elements on the periodic table. Period 3 elements are those in the third row, and they include Na, Mg, Al, Si, P, S, and Cl.
2. Compare the given ionization energies with the known ionization energies of the period 3 elements.

After comparing the given ionization energies with the known values, we can identify the element as Magnesium (Mg).
The element in period 3 with successive ionization energies (IE1 = 578, IE2 = 1820, IE3 = 2740, IE4 = 11,500, and IE5 = 13,000) is Magnesium (Mg).

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An ambidentate ligand is a type of ligand that can bond through two different atoms or groups in the same molecule.

An ambidentate ligand is a ligand that can bind to a central metal atom/ion through two different donor atoms present within the same molecule, but only one donor atom can bind at a time. This means that it can bond to a metal ion through either of these two atoms or groups. Two examples of ambidentate ligands, other than NO2, are:

1. SCN- (thiocyanate): This ligand can bind to the metal through either the sulfur (S) or the nitrogen (N) atom.
2. OCN- (cyanate): This ligand can bind to the metal through either the oxygen (O) or the nitrogen (N) atom.

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The pH of the solution after the addition of 1.11 mol HCl is 7.85.

First, we need to find the initial concentration of the weak base:

0.85 M = [B]/0.849 L

[B] = 0.85 * 0.849 = 0.72165 mol/L

Next, we can use the pKb value to find the Kb value:

pkb = -log(Kb)

7.85 = -log(Kb)

Kb = 1.74 x 10⁻⁸

Now we can set up the equilibrium expression for the weak base:

B + H2O ⇌ BH+ + OH-

Kb = [BH+][OH-]/[B]

At equilibrium, we can assume that [OH-] is negligible compared to [B] and [BH+]. This allows us to simplify the expression to:

Kb = [BH+][OH-]/[B] ≈ [BH+][OH-]/([B] + [BH+])

Since we are dealing with a weak base, we can also assume that [BH+] is much less than [B]. This allows us to simplify the expression further to:

Kb = [BH+][OH-]/[B] ≈ [BH+][OH-]/[B]

Now we can use the initial concentration of the weak base and the Kb value to find [BH+]:

Kb = [BH+][OH-]/[B]

1.74 x 10⁻⁸= [BH+]/0.72165

[BH+] = (1.74 x 10⁻⁸ * 0.72165) = 1.0138 x 10⁻⁴ M

Next, we can use the balanced chemical equation for the reaction between HCl and the weak base:

HCl + B ⇌ BH+ + Cl-

Since we are adding 1.11 mol of HCl and the weak base is the limiting reactant, all of the weak base will react with the HCl. This means that the final concentration of BH+ will be equal to the initial concentration of the weak base:

[BH+] = 0.72165 mol/L

Now we can use the Henderson-Hasselbalch equation to find the pH of the solution:

pH = pKb + log([BH+]/[B])

pH = 7.85 + log(0.72165/0.72165)

pH = 7.85

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a) The mass of 9.50 moles of calcium carbonate is 950.95 g.

b) The number of molecule in ammonia are 9.033 x 10²⁴ molecules.

c) The number of moles of H is 0.112 mol.

d) The number of molecule of methane is 9.57 x 10²³ molecules.

e) Number of moles of H atoms are2.

a. To determine how many grams of calcium carbonate are needed to weigh out 9.50 moles, we need to use the molar mass of calcium carbonate, which is approximately 100.09 g/mol. Therefore, the mass of 9.50 moles of calcium carbonate would be 9.50 mol x 100.09 g/mol = 950.95 g.

b. To calculate the number of molecules of ammonia in 15.0 moles of NH₃, we can use Avogadro's number, which is 6.022 x 10²³ molecules/mol. Thus, the number of molecules of ammonia would be 15.0 mol x 6.022 x 10²³ molecules/mol = 9.033 x 10²⁴ molecules.

c. To find the number of moles of hydrogen (H) in 26.0 g of H₂O, we need to first calculate the molar mass of H₂O. The molar mass of H₂O is approximately 18.015 g/mol. Therefore, the number of moles of H atoms in 26.0 g of H₂O can be found by dividing the mass of H in 1 mole of H₂O (2.016 g/mol) by the molar mass of H₂O: 2.016 g/mol ÷ 18.015 g/mol ≈ 0.112 mol.

d. To determine the number of molecules of CH₄ in 25.5 g of methane, we need to first calculate the molar mass of CH₄, which is approximately 16.04 g/mol. Then, we can use Avogadro's number to convert from moles to molecules: 25.5 g / 16.04 g/mol = 1.59 mol, and 1.59 mol x 6.022 x 10²³ molecules/mol ≈ 9.57 x 10²³ molecules.

e. To determine the number of moles of hydrogen (H) atoms, we need to know the number of moles of the compound that contains them. If we consider water (H₂O) as an example, we can find the number of moles of H atoms by using the same approach as in part c. In one mole of H₂O, there are two moles of H atoms. Therefore, to find the number of moles of H atoms, we can simply multiply the number of moles of H₂O by 2.

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The question cannot be answered without more information. The configuration of each chiral center needs to be specified as either R or S, as they have opposite configurations.

Chirality refers to the property of a molecule or ion that is not superimposable on its mirror image. Chiral centers are atoms in a molecule that are bonded to four different groups, and their configuration can be described using the R/S nomenclature system. The R and S designations are based on the priority of the four substituent groups around the chiral center, which is determined by the atomic number of the attached atoms. Without knowing the specific configuration of each chiral center, it is impossible to determine the chirality of the (1,2) chiral centers.

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NH3(g) will be present in higher amounts when the system is in equilibrium.

A very high value of K suggests that most of the reactants are transformed into products at equilibrium. The ratio of product concentrations to reactant concentrations raised to the proper stoichiometric coefficients is the equilibrium constant K.

Yes, the equilibrium constant does fluctuate as the temperature changes. As the temperature drops, the exothermic reaction's equilibrium constant drops as well. However, in an endothermic reaction, the equilibrium constant rises as the temperature rises.

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Hence, 1.14 moles of Sulfur dioxide in 73 g and 44 grams of Carbon dioxide are in 1 mole.

The first question asks us to find the number of moles of sulfur dioxide in 73.0 grams. We can use the formula:

Moles = mass / molar mass,

where molar mass is the sum of the atomic masses of all the elements in the compound. For sulfur dioxide, the molar mass is 32.07 g/mol for sulfur and 2*16.00 g/mol for oxygen, giving a total of 64.07 g/mol.

Plugging in the given mass of 73.0 g and the molar mass, we get the number of moles to be 1.14 mol, which corresponds to option (c).

The second question asks us to find the mass of carbon dioxide in 1.00 mole. We can use the formula:

Mass = moles * molar mass,

where the molar mass is 12.01 g/mol for carbon and 2*16.00 g/mol for oxygen, giving a total of 44.01 g/mol for carbon dioxide. Plugging in the given number of moles of 1.00 mol and the molar mass, we get the mass to be 44.0 g, which corresponds to option (c).

Therefore, the answer to both questions is (c) 1.14 mol for the first question and 44.0 g for the second question.

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Yes, Bromcresol Purple would be an appropriate indicator for the titration of a strong acid with a strong base.

During a titration, an indicator is used to signal the endpoint or equivalence point of the reaction. Bromcresol Purple is a pH indicator that changes color in the pH range of 5.2 (yellow) to 6.8 (purple).

In the titration of a strong acid with a strong base, the equivalence point occurs at pH 7, which is close to the color change range of Bromcresol Purple. Therefore, Bromcresol Purple is suitable for this titration as it can accurately indicate when the strong acid has been neutralized by the strong base.

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The theoretical yield of NaCl when you mix 2.00g of Na2CO3 is 2.21g.  Use the balanced equation's stoichiometry to determine the NaCl moles produced. To calculate the theoretical yield of NaCl when mixing 2.00g of Na2CO3, we need to first consider the balanced chemical equation for the reaction between Na2CO3 and HCl:

Na2CO3 + 2HCl -> 2NaCl + CO2 + H2O

This equation shows that one mole of Na2CO3 reacts with two moles of HCl to produce two moles of NaCl. We can use this information to calculate the theoretical yield of NaCl by following these steps:

1. Convert 2.00g of Na2CO3 to moles by dividing by its molar mass (105.99 g/mol).

2. Use stoichiometry to determine the moles of NaCl produced. Since the reaction produces two moles of NaCl for every mole of Na2CO3, we can multiply the moles of Na2CO3 by 2 to get the moles of NaCl.

3. Convert the moles of NaCl to grams by multiplying by its molar mass (58.44 g/mol).

The calculation looks like this:

2.00g Na2CO3 x (1 mol Na2CO3/105.99 g Na2CO3) x (2 mol NaCl/1 mol Na2CO3) x (58.44 g NaCl/1 mol NaCl) = 2.78g NaCl (theoretical yield)

Therefore, the theoretical yield of NaCl when mixing 2.00g of Na2CO3 is 2.78g.

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Reagents to convert acetylene into 2-pentyne are found in 1) NaNH₂; 2) CH₃I; 3) NaNH₂; 4) CH₃CH₂I.

So, the correct answer is B.

To synthesize 2-pentyne from acetylene, you need to perform two nucleophilic substitution reactions. First, acetylene is treated with NaNH₂ (sodium amide), a strong base, which removes a hydrogen atom from acetylene, generating an acetylide anion. This anion acts as a nucleophile and reacts with CH₃I (methyl iodide), forming 1-butyne. Then, 1-butyne is treated again with NaNH₂, generating another acetylide anion. Finally, this anion reacts with CH₃CH₂I (ethyl iodide), yielding the desired product, 2-pentyne.

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To determine the most effective buffer made by HNO2 and NaNO2 with a pH of 3.15, we need to calculate the ratio of the concentrations of the conjugate acid-base pair (HNO2 and NO2-) that will give the desired pH.

The pH of the buffer solution can be calculated using the Henderson-Hasselbalch equation:

pH = pKa + log([A-]/[HA])

where pKa is the acid dissociation constant of the weak acid, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the weak acid.

Substituting the given values:

pH = -log(7.11 x 10^-4) + log([NO2-]/[HNO2])

3.15 = 3.15 + log([NO2-]/[HNO2])

log([NO2-]/[HNO2]) = 0

[NO2-]/[HNO2] = 1

Therefore, the most effective buffer will be made by mixing HNO2 and NaNO2 in a 1:1 molar ratio. This will give a pH of 3.15 and will be able to resist changes in pH when small amounts of acid or base are added to the solution.

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When KBr was added to the copper sulphate solution, the concentration of bromide ions (Br-) increases, the concentration of Cu(H2O)6+2 ions decreases and the concentration of CuBr4-2 ions increases.

When potassium bromide (KBr) was added to the copper sulphate solution, the following changes in the concentration of ions occurred:
1. The concentration of bromide ions (Br-) increased due to the addition of KBr.
2. The equilibrium shifted to the right i.e, forward reaction , as more Br- ions reacted with Cu(H2O)6+2 ions to form CuBr4-2 ions.
3. As a result, the concentration of Cu(H2O)6+2 ions decreased, and the concentration of CuBr4-2 ions increased.
This shift in equilibrium led to a change in colour from blue (due to Cu(H2O)6+2 ions) to green (due to CuBr4-2 ions).

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Answer:

2) It is less than before the tax was imposed.

A portion of the tax that is levied on a commodity must be paid by the seller, which lowers their profit margin. Sellers will raise the cost of the good and pass this cost onto purchasers in order to preserve their profit. This causes the market price that buyers must pay to rise as a result of taxation.

When an action potential reaches a neuromuscular junction, it triggers the release of acetylcholine into the synaptic cleft.

The acetylcholine then binds to the nicotinic receptors, which are concentrated on the motor end plate of the muscle fiber's post-synaptic membrane. This binding causes the opening of ion channels and the influx of positively charged ions, which results in depolarization of the muscle fiber's membrane. This depolarization then spreads through the muscle fiber, ultimately leading to muscle contraction. The action of acetylcholine at the neuromuscular junction is critical for normal muscle function and is targeted by many drugs used to treat neuromuscular disorders.

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When 2 x 10⁵ dyn of force is applied along its length, the initial length (l) becomes (c) 2l.

First convert the given values to the appropriate units and then use the formula for Young's modulus.

Young's modulus (Y) = 10⁴ N/m²
Area of cross-section (A) = 2 cm² = 2 x 10⁻⁴ m² (since 1 cm² = 10⁻⁴ m²)
Force (F) = 2 x 10⁵ dyn = 2 N (since 1 N = 10⁵ dyn)

Young's modulus (Y) = Stress/Strain = (F/A)/(Δl/l)

We need to find the change in length (Δl) with respect to the initial length (l).

Rearranging the formula: Δl/l = F/(Y × A)

Now, substitute the given values:

Δl/l = 2 N / (10^4 N/m² × 2 x 10^-4 m²) = 1

Thus, Δl = l

The initial length becomes l + Δl = l + l = 2l. So the correct answer is option C, 2l.

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