The heat of fusion AH, of methanol (CH,OH) is 3.16 kJ/mol. Calculate the change in entropy AS when 9.8 g of methanol freezes at -98.0 ยฐC.

The correct order of nucleophilicity from best to worst is option B: RO-, RHN-, RH2C-.

Explanation: Nucleophilicity is the ability of an atom or molecule to donate an electron pair to an electrophile, forming a new bond. The order of nucleophilicity depends on the ability of the nucleophile to donate its electron pair. In this case, we have three nucleophiles: RO-, RHN-, and RH2C-.

1. RO- is an alkoxide ion, which has a negative charge on the oxygen atom. Oxygen is more electronegative and is better at stabilizing the negative charge, making it a strong nucleophile.
2. RHN- is an amide ion, which has a negative charge on the nitrogen atom. Nitrogen is less electronegative than oxygen, so it is less capable of stabilizing the negative charge. This makes RHN- a moderately strong nucleophile.
3. RH2C- is a carbanion, which has a negative charge on the carbon atom. Carbon is even less electronegative than nitrogen, so it is the least capable of stabilizing the negative charge, making RH2C- the weakest nucleophile.

Conclusion: Considering the electronegativity and the ability to stabilize the negative charge, the correct order of nucleophilicity from best to worst is RO-, RHN-, RH2C- (option B).

To know more about nucleophilicity, visit

https://brainly.com/question/19578949

#SPJ11

When pH is less than pKa, the group is in its protonated form.

When pH is less than pKa, the concentration of H⁺ ions in the solution is greater than the concentration of the group's conjugate base, so the group tends to attract H⁺ ions and become protonated. Conversely, when pH is greater than pKa, the group is in its deprotonated form, meaning that it has lost a hydrogen ion and become more basic.

In the context of acid-base chemistry, pKa is a measure of the acidity of a molecule, while pH indicates the hydrogen ion concentration in a solution. When pH is less than the pKa value of a group, it means the solution is more acidic, and thus, the group tends to exist in its protonated (or more positively charged) form.

To know more about protonated visit:-

https://brainly.com/question/20373356

#SPJ11

1: When 1.35 moles of oxygen are reacted with aluminum, 2 moles of aluminum will be used.

This is because the chemical equation for the reaction is Al + O2 → 2Al2O3, and thus, for every mole of oxygen, two moles of aluminum will be used.

2: When 0.0240 moles of sodium are reacted with hydrogen, 0.0240 moles of hydrogen will be produced.

This is because the chemical equation for the reaction is Na + H2O → NaOH + H2, and thus, for every mole of sodium, one mole of hydrogen will be produced.

Learn more about sodium at:

https://brainly.com/question/29327783

#SPJ1

Carboxylic acids are strong organic acids because their conjugate base is resonance stabilized.

If we talk about the carboxylic acid then we mean the kind of acid that we can be able to represent by the use of the general formula that is written as RCOOH where R would stand in for any of the alky groups.

When we remove the proton from the carboxylic acid then we form the carboxylate ion which can be resonance stabilized. The carboxylate anion (the conjugate base of a carboxylic acid) can resonate between two forms, each with a negative charge on one of the oxygen atoms.

Learn more about carboxylica acid:https://brainly.com/question/1852102

#SPJ1

Carboxylic acids are strong for organic acids because Their conjugate base is resonance stabilized. Option B

Carboxylic acids are natural acids with a carbon atom and a carboxyl group (-COOH). Considering that their bases are resonance stabilized, they are known to be really strong organic acids.

It is known that the negative charge of a carboxylate anion is delocalized over two oxygen atoms via resonance. This stabilizes the anion and makes it less likely to release a proton.

When you compare Carboxylic acids  to other organic acids that lack this resonance stabilization quality, carboxylic acids are stronger acids.

Find more exercises linked to the term Carboxylic acids;

https://brainly.com/question/31480248

#SPJ1

A strong tendency to undergo oxidation and a strong tendency to undergo reduction creates a large difference in charge and therefore a high cell potential.

In an electrochemical cell, the difference in charge is created by the transfer of electrons between the two half-reactions. Oxidation and reduction reactions involve the transfer of electrons from one atom to another. When a substance undergoes oxidation, it loses electrons, while in reduction, it gains electrons. This transfer of electrons results in a difference in charge, which generates an electric potential between the two substances. The greater the difference in charge, the higher the cell potential.
In a galvanic cell, the anode undergoes oxidation and the cathode undergoes reduction, leading to the production of electrical energy. Therefore, a strong tendency for oxidation and reduction to occur will result in a higher cell potential, which means more electrical energy can be generated.
In summary, the strong tendency to undergo oxidation and reduction creates a large difference in charge and, therefore, a high cell potential, leading to the production of electrical energy in a galvanic cell.

Learn more about cell here:

https://brainly.com/question/12034258

#SPJ11

This type of pigmentation color harmony is known as a monochromatic color scheme.

Your question is about pigmentation color harmonies where one color and its tints and shades are placed side by side without mixing.
In a monochromatic color scheme, one base color is chosen, and its various tints and shades are used to create the harmony. This color scheme is achieved by adding white or black to the base color to create different shades and tints, without mixing it with other colors. The result is a visually cohesive and harmonious color palette with a single dominant hue.

Learn more about Pigments: https://brainly.com/question/30808713

#SPJ11

The desorption of the bromine (Br) atom from the surface will result in an increase in entropy. This is because the system now has more possible arrangements of the remaining chlorine (Cl) atom on the surface. Initially, there were 36 possible adsorption sites for the two atoms.

After the desorption of the Br atom, there are only 35 sites left for the Cl atom to occupy. Therefore, the change in entropy (ΔS) can be calculated using the equation: ΔS = k ln(Wf/Wi) where k is the Boltzmann constant, Wf is the final number of possible arrangements and Wi is the initial number of possible arrangements. Wi = 36 × 36 = 1296 (since there were 36 possible adsorption sites for each of the two atoms) Wf = 36 × 35 = 1260 (since there are now 35 possible sites for the Cl atom) ΔS = k ln(1260/1296) ΔS = (1.38 × 10^-23 J/K) ln(0.97) ΔS = -2.24 × 10^-25 J/K (rounded to 2 significant digits) The unit for entropy is joules per Kelvin (J/K). Therefore, the change in entropy is -2.24 × 10^-25 J/K, indicating a slight decrease in entropy due to the loss of one possible arrangement of the atoms on the surface.

Learn more about bromine here-

https://brainly.com/question/29028678

#SPJ11

Entropy (S) is a measure of molecular randomness or disorder and its change (ΔS) is a state function that depends only on initial and final states. The answer is b.

ΔS has a positive value when disorder increases and a negative value when disorder decreases. Increase in entropy is usually observed in a change of phase, an increase in the number of gas molecules, or a solid dissolving to form a solution.

Entropy (S) is a measure of disorder or randomness at a molecular level. The change in entropy (ΔS) is a state function that depends only on the initial and final states of the system. The ΔS has a positive value when the disorder increases and a negative value when the disorder decreases.

The entropy of a system usually increases when a change of phase occurs, for example, when a solid changes to a liquid and then to a gas. An increase in the number of gas molecules also results in an increase in entropy. The third condition that usually results in an increase in entropy is when a solid dissolves to form a solution.

These processes represent an increase in disorder at the molecular level and lead to an increase in the overall entropy of the system.

To know more about Entropy, refer here:
https://brainly.com/question/14131507#
#SPJ11

Answer:

Explanation:

To solve this problem we'll use the Henderson-Hasselbach equation, but first we need the vale for the pKa of Benzoic acid, which is pKa= -log(Ka)=4,19

Now, we apply the equation as follows:

So, the pH of this solution of Sodium Benzoate and Benzoic Acid is 3,97

Have a nice day!

To determine the slope and calculate the experimental value of ε, the extinction coefficient, for Allura Red, you first need to measure the absorbance of different concentrations of Allura Red using a spectrophotometer.

Then, plot the absorbance against the concentration of Allura Red and determine the slope of the line. The slope of the line represents the value of the extinction coefficient, ε. To calculate the experimental value of ε, divide the slope by the path length of the cuvette used in the spectrophotometer.

The extinction coefficient is a measure of how much light a substance absorbs at a particular wavelength, and it varies depending on the wavelength and the specific substance being measured.

By determining the extinction coefficient for Allura Red, scientists can use this information to quantitatively measure the amount of Allura Red present in a sample based on its absorbance at a specific wavelength.

It is important to calculate the experimental value of ε accurately as it impacts the accuracy of the measurement of the concentration of Allura Red in a sample.

To know more about the  Allura Red refer here:

https://brainly.com/question/15698414#

#SPJ11

The half-life (t1/2) for the reaction in the illustration can be calculated using the first-order rate law equation: ln([A]/[A]0) = -kt. Here, [A]0 represents the initial concentration of compound x and [A] represents its concentration at a given time.

Since the reaction is first-order, the rate constant (k) is constant throughout the reaction. Therefore, the half-life can be calculated using the following equation: t1/2 = (ln 2)/k.

Without knowing the specific values of [A] and [A]0, it is not possible to calculate the exact half-life for this reaction. However, it can be concluded that the half-life for this slow, first-order transformation from compound x to y would be relatively long, as the reaction is slow.

To know more about the half-life refer here :

https://brainly.com/question/24710827#

#SPJ11

A 0.873 g sample of magnesium chloride dissolves in 95 g of water in a flask. the number of moles of cl is 0.0183  

To calculate the number of moles of Cl in the solution, we need to first determine the number of moles of magnesium chloride in the solution.
The formula for magnesium chloride is [tex]MgCl_{2}[/tex], so the molar mass is:
24.31 g/mol (Mg) + 2(35.45 g/mol) (Cl) = 95.27 g/mol
We can use this molar mass to convert the mass of magnesium chloride in the solution to moles:
0.873 g / 95.27 g/mol = 0.009171 moles [tex]MgCl_{2}[/tex]
Since magnesium chloride contains 2 moles of Cl for every mole of [tex]MgCl_{2}[/tex], we can multiply the number of moles of [tex]MgCl_{2}[/tex] by 2 to find the number of moles of Cl in the solution:
0.009171 moles [tex]MgCl_{2}[/tex] x 2 moles Cl / 1 mole [tex]MgCl_{2}[/tex] = 0.01834 moles Cl
Rounding to 4 decimal places, the answer is 0.0183 moles Cl.

Learn more about molar mass here:

https://brainly.com/question/30640134

#SPJ11

The kind of reaction that occurs when the overall entropy change is negative is endothermic (option A).

Endothermic reaction is a chemical reaction that absorbs heat energy from its surroundings.

In an endothermic reaction, the external entropy (entropy of the surroundings) decreases.

If a reaction is endothermic (H positive) and the entropy change (∆S) is negative (less disorder), the free energy change is always positive and the reaction is never spontaneous.

Learn more about endothermic reaction at: https://brainly.com/question/23184814

#SPJ1

Assuming 100% yield, the mass of the resulting polymer would also be 26.39 kg.

To produce poly(ethylene terephthalate), a linear chain structure, ethylene glycol must be added to dimethyl terephthalate in a 1:1 molar ratio.

Since the molar mass of ethylene glycol is 62 g/mol and the molar mass of dimethyl terephthalate is 194 g/mol, the mass of ethylene glycol required to react with 20 kg of dimethyl terephthalate can be calculated as:
(20 kg / 194 g/mol) x (1 mol ethylene glycol / 1 mol dimethyl terephthalate) x (62 g/mol) = 6.39 kg of ethylene glycol
Therefore, 6.39 kg of ethylene glycol must be added to 20 kg of dimethyl terephthalate to produce poly(ethylene terephthalate).
The resulting polymer mass can be calculated based on the total mass of the reactants (20 kg dimethyl terephthalate + 6.39 kg ethylene glycol = 26.39 kg).

To learn more about ethylene glycol click here https://brainly.com/question/10405060

#SPJ11

When phenol red turns yellow, it means that the solution has become acidic. Phenol red is a pH indicator that changes color depending on the acidity or alkalinity of a solution. In neutral or alkaline conditions, phenol red remains red, but when the pH drops below 6.8, it turns yellow.

This color change occurs because phenol red is sensitive to changes in the concentration of hydrogen ions (H+) in a solution. When a solution becomes more acidic, it means that there is a higher concentration of hydrogen ions, which react with the phenol red to produce the yellow color.
Phenol red is commonly used in biology and chemistry experiments to monitor changes in pH. For example, in cell culture, phenol red is added to the media to indicate whether the pH of the solution is within the optimal range for cell growth. In microbiology, phenol red is used to detect acid production by bacteria, as some bacteria can produce acidic byproducts that change the color of phenol red to yellow.
In summary, when phenol red turns yellow, it indicates that the solution has become acidic due to an increase in hydrogen ion concentration.

For more such questions on phenol

https://brainly.com/question/9512716

#SPJ11

The energy diagram for the SN1 reaction of t-butyl bromide in water can be described by the following statements.
The carbocation intermediate is more stable than the starting material This statement is incorrect. In the SN1 reaction, the carbocation intermediate is less stable than the starting material due to its positive charge.

The statement is correct. In the SN1 reaction, the first transition state has a higher energy level than the second transition state because it involves breaking a bond to form the carbocation intermediate, which is an energetically unfavorable process. The first step of the reaction is exothermic This statement is incorrect. The first step of the SN1 reaction, which involves breaking the bond between the t-butyl group and the bromine atom, is endothermic. This is because energy is required to break the bond and form the less stable carbocation intermediate.  The energy diagram for the SN1 reaction has two energy maxima, corresponding to the two transition states - one for the formation of the carbocation intermediate and another for the nucleophilic attack by water.  The energy of the carbocation intermediate is at an energy minimum between the two transition states. The energy maxima represent the transition states, while energy minima correspond to stable species (reactants, intermediates, and products) in the reaction.

learn more about t-butyl bromide here.

https://brainly.com/question/31462536

#SPJ11

The Chemical reaction - MgCO₃ + 2HCl = MgCl₂ + H₂O + CO₂ is a neutralization reaction.

A neutralization reaction can be defined as a chemical reaction in which an acid and base quantitatively react together to form a salt and water as products.

In a reaction to water, neutralization results in excess hydrogen or hydroxide ions present in the solution. The pH of the neutralized solution depends on the strength of the acid or base involved in it.

In this reaction MgCO₃ acts as base undergoing reaction with HCl to give salt, water and Carbon dioxide.

Learn more about Neutralization, here:

https://brainly.com/question/15347368

#SPJ1

The "1" in the phrase "SN1 Reaction" indicates the rate order of the reaction.

SN1 stands for substitution nucleophilic unimolecular, which means that the reaction involves a single molecule in the rate-determining step.

This reaction occurs in two steps, with the first step being the formation of a carbocation intermediate.

The stereochemical outcome of an SN1 reaction is often a racemic mixture because the carbocation intermediate can be attacked from either side by a nucleophile.

However, the "1" does not indicate the stereochemical outcome specifically, but rather the fact that the reaction occurs through a single molecule in the rate-determining step.

Equilibrium is not directly related to the SN1 reaction, as the reaction is a uni-directional process.

Therefore, the correct answer is D, the rate order.

In the context of the "SN1 Reaction," the "1" indicates the rate order (option D).

SN1 reactions, which stands for "Substitution Nucleophilic First Order," are characterized by their first-order kinetics, meaning the reaction rate is directly proportional to the concentration of one reactant.

In SN1 reactions, the nucleophile substitution process involves a two-step mechanism: the formation of a carbocation intermediate and the subsequent nucleophilic attack. The stereochemical outcome of an SN1 reaction typically results in racemization, as the nucleophile can attack from either side of the planar carbocation intermediate.

The "1" does not refer to the equilibrium constant, the number of reactants involved, or the stereochemical outcome, but rather the rate order of the reaction.

To know more about SN1 Reaction: brainly.com/question/10666011

#SPJ11

The forces that makes human work difficult are Frictional Force, Gravitational Force, and Tension Force.

Frictional Force:

Friction is the force that prevents solid surfaces, fluid layers, and material elements from sliding against each other.

Gravitational Force:

The force of attraction exerted on a body by the earth is known as gravitational force.

Tension Force:
Tension is described as the force transferred through a rope, string, or wire when it is pulled by opposing forces.

Learn more about forces here:

https://brainly.com/question/12970081

#SPJ1

The best description of the result of the addition of a small amount of solid NaNO2 to a solution of HNO2 is that it will increase the concentration of NO2- ions, thereby increasing the pH of the solution.

This is because NaNO2 will dissociate into Na+ and NO2- ions in the solution, and the NO2- ions will react with HNO2 to form more HNO3 and NO. The increase in NO2- ions will lead to a shift in the equilibrium of the reaction, ultimately increasing the pH of the solution.

To undertsnad what is an addition reaction : https://brainly.com/question/1433809

#SPJ11

The precursors for the biosynthesis of the pyrimidine ring system include carbamoyl phosphate and aspartate. Carbamoyl phosphate is produced from the reaction between ammonia NH3 and carbon dioxide CO2, while aspartate is derived from the amino acid glutamine.

The glutamine indirectly contributes to the biosynthesis of the pyrimidine ring system by providing the precursor molecule aspartate. The precursors for the biosynthesis of the pyrimidine ring system include carbamoyl phosphate and aspartate. In this process, the biosynthesis of pyrimidines involves the formation of the pyrimidine ring system using carbamoyl phosphate and aspartate as the main precursors. The carbamoyl phosphate is generated from glutamine and CO2, while aspartate provides the additional atoms needed to form the ring structure.

learn more about biosynthesis here

https://brainly.com/question/13269447

#SPJ11

The pKa of PhSCH2NO2 is around 8.5 at a pH of 7. However, the pKa value can change depending on the pH of the solution, with lower pH values resulting in a stronger acid and higher pH values resulting in a weaker acid.

The pKa of PhSCH2NO2 is a measure of the acidity of the molecule. The term pKa refers to the negative logarithm of the acid dissociation constant, which is a measure of the strength of an acid. The lower the pKa value, the stronger the acid is.

In the case of PhSCH2NO2, the pKa value can vary depending on the pH of the solution. At a pH of 7, which is neutral, the pKa of PhSCH2NO2 is around 8.5.

This means that at pH 7, only a small percentage of the molecules will be in the protonated form, and most will be in the deprotonated form.

However, if the pH of the solution is lower than the pKa value, the molecule will be mostly in the protonated form, and if the pH is higher, it will be mostly in the deprotonated form.

The pH value of a solution is a measure of the concentration of hydrogen ions (H+) present in the solution. A pH of 7 is neutral, while a pH lower than 7 is acidic and a pH higher than 7 is basic.


The pKa of a compound is a measure of its acidity, and it is the negative logarithm of the acid dissociation constant (Ka). The pH represents the concentration of hydrogen ions in a solution and ranges from 0 to 14.

A lower pH indicates a more acidic solution, while a higher pH indicates a more basic solution.

Regarding the compound PhSCH2NO2, it's important to note that specific pKa values are typically found in a database or determined experimentally. I am unable to provide the exact pKa value for this compound, as I don't have access to an appropriate database.

In general, pKa values help us understand the relative acidity or basicity of a compound and can be used to predict the behavior of that compound in different chemical reactions.

Visit here to learn more about Molecules:

brainly.com/question/475709

#SPJ11

The nitromethane molecule, CH₃NO₂, can have two resonance structures. Resonance structures are alternate forms of a molecule that differ only in the distribution of electrons and can be represented using curved arrows to indicate the movement of electrons. In the case of nitromethane, there are two major resonance structures that contribute to the stability of the molecule.

The first resonance structure involves the movement of a lone pair of electrons from the nitrogen atom to form a double bond with one of the oxygen atoms. This results in a positive charge on the nitrogen atom and a negative charge on the oxygen atom.

The second resonance structure involves the movement of a double bond between the nitrogen and one of the oxygen atoms to form a single bond, and the movement of a lone pair of electrons from the other oxygen atom to form a double bond. This results in a negative charge on one oxygen atom and a positive charge on the other.

Both of these resonance structures contribute to the stability of the nitromethane molecule and play a role in its reactivity in various chemical reactions.

To know more about nitromethane molecule refer here:

https://brainly.com/question/19578949#

#SPJ11

Electron rich species are those that have an excess of electrons in their outer shell. These species are typically negatively charged and have a high electron density.

The relationship between electron rich and electron deficient species is one of attraction and repulsion. Electron rich species are attracted to electron deficient species because they have a surplus of electrons that they can donate to the electron deficient species. This is known as a nucleophilic reaction.

                                             On the other hand, electron deficient species are those that have a shortage of electrons in their outer shell. These species are typically positively charged and have a low electron density.


On the other hand, electron deficient species are attracted to electron rich species because they have a shortage of electrons that they can accept from the electron rich species. This is known as an electrophilic reaction.

Overall, the relationship between electron rich and electron deficient species is one of balance. They work together to maintain a stable electronic configuration and to achieve chemical equilibrium.

Learn more about electrophilic reaction

brainly.com/question/31538041

#SPJ11

The electrode in any half cell with a greater tendency to undergo reduction is negatively charged and therefore has a more positive E.

In any half-cell, the electrode with a greater tendency to undergo reduction is positively charged and therefore has a higher (more positive) E. This is because a higher reduction potential (E) indicates a greater tendency for the species to accept electrons and undergo reduction, resulting in a positive charge on the electrode.

Electrode potential in electrochemistry is the electromotive force of a galvanic cell constructed from a reference electrode that is considered to be standard and a test electrode. Standard hydrogen electrode (SHE) is the reference electrode by convention. It is stated that it has a potential of 0 volts.

More on electrode: https://brainly.com/question/28188023

#SPJ11

The ammonia concentration of the aqueous solution is approximately 1.8 times 10^-2 M.

To determine the ammonia concentration of an aqueous solution with a pH of 11.00, we need to first find the concentration of hydroxide ions (OH-) present in the solution.

Using the pH equation, we can find that the concentration of OH- is 1.0 x 10^-3 M.

Next, we can use the equilibrium equation for the dissociation of NH3 to calculate the concentration of ammonia (NH3).

We know that Kb = [NH4+][OH-]/[NH3], and we have the value for Kb and [OH-].

We can assume that the concentration of NH4+ is negligible compared to the concentration of NH3, so we can simplify the equation to Kb = [OH-][NH3].

Rearranging the equation, we get [NH3] = Kb/[OH-] = (1.8 x 10^-5)/(1.0 x 10^-3) = 0.018 M.

Therefore, the answer is C) 1.8 times 10^-2 M.

To know more about equilibrium equation: brainly.com/question/31027606

#SPJ11

Therefore It is acidic.  When a weak acid and a weak base react, they form a salt that can undergo hydrolysis in water

In this case, the salt formed is C6H5NH3F (anilinium fluoride). Anilinium ion (C6H5NH3+) is a weak acid and fluoride ion (F-) is a weak base. When anilinium fluoride is dissolved in water, it undergoes hydrolysis, producing H+ ions from the anilinium ion and OH- ions from the fluoride ion. In this case, since HF is a weaker acid than aniline is a base, the solution will be acidic.

Since the anilinium ion is a weak acid, it will not completely dissociate into H+ ions, resulting in a lower concentration of H+ ions compared to OH- ions. Therefore, the solution will be basic.

However, since there is no information about the concentration of anilinium fluoride and the degree of hydrolysis, it is not possible to determine the pH of the solution accurately. Therefore, the correct answer is that there is not enough information.

To know more about anilinium fluoride  visit:

brainly.com/question/3795082

#SPJ11

The solubility and rate of dissolution are related in that an increase in the rate of dissolution usually leads to an increase in the solubility of the solute. This is because of the increased movement and collisions of particles in the solution due to increased temperature or agitation.

Solubility is a measure of the maximum amount of solute that can dissolve in a given amount of solvent under specific conditions, such as temperature and pressure. For example, at a specific temperature and pressure, a certain amount of sugar can dissolve in a cup of water to form a homogeneous solution, but adding more sugar than this amount will result in the excess sugar remaining undissolved at the bottom of the cup.

Learn more about solubility here.

https://brainly.com/question/14092437

#SPJ1

The dichotomous key for the identification of gram-positive bacteria, the next test you would do after identifying a gram-positive staphylococcus that is positive for catalase production but negative for coagulase is to make a lawn of bacteria on a Mueller Hinton agar plate and test for novobiocin sensitivity.

The information provided, if you have identified a Gram-positive staphylococcus that is positive for catalase production but negative for coagulase, the next test to perform according to the dichotomous key for the identification of Gram-positive bacteria (found in Experiment 16 ppt) would be to make a lawn of bacteria on a Mueller Hinton agar plate and test for novobiocin sensitivity.

learn more about bacteria here.

https://brainly.com/question/14805232

#SPJ11