Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors, 

I thank you for the opportunity of reading your work, which can be an important contribution to the metallurgical field. However, some major revisions are necessary, in order to improve the article's content, especially regarding the physical discussion of the results and description of some modelling strategies.

Best Regards.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Text is confusing to understand in some important paragraphs. Also, English quality can be improved. I recommend the authors to check the entire document, and try to, whenever possible, to improve the text's quality.  

Author Response

Comments [1]: Lines 31. Authors must create a stronger technological link. Simolicity by it self should not be, in my oppinion, a reason for the study, but an interesting characteristic of the phenomena.

Response [1]: I have added a sentence: "Furthermore, dissolution is important in diverse fields, from dentistry where it is important in understanding tooth decay, to geochemistry, where dissolution controls the dissolved mineral content of fresh water, through to chemical processes, where leaching in hydrometallurgy is dissolution in industrial action."

Comment [2]: Authors could include some examples of applications of this knowledge considering industrial opperations.

Response [2]: Same as for Response [1].

Comments [3]: in comparison to more

Response [3]: Thank you. Changed to “by the rate of film diffusion”.

Comments [4]: English of this paragraph can be improoved.

Response [4]: Replaced “a” with “the”.

Comments [5]: Linear and non-linear behaviors must be better defined in text. .

Response [5]: Changed to “These values vary between linear, where  is equal to 1, and highly non-linear, where  is significantly greater than 1.”

Comments [6]: are (in respect to line 50).

Repsonse [6]: Corrected in Response [5].

Comments [7]: text format can be improved.

Response [7]: Publishers response required.

Comments [8]: Authors must better explain this fact in text. Why equation 6 can not be applief for such a condition?

Response [8]: Although the paragraph is written correctly, I can see why the reviewer might require a better explanation. I have changed this to read: “Like , the reported values of  have a large range. For example, the value of varies between 2 and 4 for calcite and aragonite depending on the experimental conditions (Romanek et al., 2011). The critical weaknesses of Eq. (2) that (i) it does not represent the rate when the concentrations of anions and cations are not equal, and (ii) it does not reduce to the correct thermodynamic form yielding the solubility product when the rate is zero. These weaknesses are addressed by Eq. (7); however, Eq. (7) does not address the wide spread of values reported for the parameter , nor does it provide any insight into why the kinetics are linear for some minerals, for example, gypsum, and non-linear for others, like AgCl.”

Comments [9]: Authors must better explain this conclusion. What they mean by thermodynamic form? when r in eq. 6 is zero, Cs and C are equal, and thermodynamic equilibrium is achieved.

Response [9]: I was referring to Eq. (2), which when r is zero does not yield the solubility product. The change in Response [8] addresses this.

Comments [10]: Authors must explain in text why this chemical potential difference is relevant in the present contex.

Response [10]: Not chemical potential. Potential means electrical. I have attempted to make this clear by adding: “due to the formation of surface charge”.

Comments [11]: I do not think that these figures should be included. They would be interesting for a review paper, which is not the present case. I suggest that authors remove them and include in a more objective way the main features of them in text.

Response [11]: I respectfully disagree. Here I am summarizing the state of the field, and many researchers due not realise that salts in solution display an electrical surface charge. If I said so, without displaying data, my statement would be dismissed. The figures support the line of reasoning perfectly well without becoming a review.

Comments [12]: Why such difference would be important?

Response: [12]:  I have added at the end of the change referred to in Response [10] “The presence of a surface charge during dissolution must influence the rate of removal of ions from the surface.”

Comments [13]: Figure 3 should be removed and main conclusions from this reference must be included and liked to present discussion.

Response [13]: Respectfully, disagree, this ignored result, it at the hear of what I am trying to develop a model for. To remove it is simply not possible.

Comments [14]: can be also applicable

Response [14]: Changes to “applies”

Comments [15]: Authors must include a brief explanation why they have chosen these salts in particular.

Response [15]: We have chosen them – this is what has been published before. I have added references.

Comment [16]: Recent refferences must be added in order to support this information.

Response [16]: Reference added.

Comment [17]: include a proper reference for equation 13.

Response [17]: reference added.

Comment [18]: Physical nature of "k" parameters must be clear discussed in text.

Response [18]: Added: “ and are the electrochemical rate constants for the anion and the cation,”

Comment [19]: include a proper reference in order to support this information.

Response [19]: reference added.

Comment [20]: a proper justification must be included in text.

Response [20]: The answer is this the next sentence, but clearly this needs to be rewritten if it is not that clear. I have changed to: “This ionic form is used as a hypothesis of this work because the bonding of the sparingly soluble is ionic in nature.”

Comment [21]: reviewer delete some text

Response [21]: I have changed the equation numbering to accommodate reviewers observation.

Comment [22]: authors must include a minimal justification for this assumption.

Response [22]: Justification was proved in a few sentences above, but this might be too far away for the readers. So I have moved it closer to this sentence.

Comment [23]: Loose sentence. Its meaning must be made clearer.

Response [23]:Changed to: “Eq. (19) indicates that  and  are potential-determining ions during dissolution or crystallization”

Comment [24]: meaning of k2 is missing.

Response [24]: apologies, lost by mistake. Added.

Comment [25]: What litersture says about it? is this consistent with results already explored in literature.

Response [25]: This is clearly what makes dissolution of salts ‘simple’. Far from equilibrium, and without mass transfer effects, they just dissolve. One doesn’t need literature to know this.

Comment [26]: Authors must explain the main steps for deduction of equation 25.

Response [26]: I have added: “The expression for the rate of growth can be obtained by returning to Eqs. (16) and (17) using only the terms describing the reverse reaction and then follow the same method as that used to get to Eq. (20). Alternatively, if it is assumed that in Eq. (20), and simplifying, the same resul can be achieved”

Comment [27]: Confuse sentence. Consider rewritting it.

Response [27]: word “mechanism” had been deleted by mistake. Added.

Comment [28]: Inform the chemical formula of Gypsium.

Response [28]: added formula

Comment [29 and 30]: This explanation must be placed just after the definition of this relationship.

Response [29 and 30] Respectfully, I prefer my order, by I have added some changes before eq. (27) and changed the paragraph to “The assumption that   was made so that the denominator of Eq. (26) was symmetrical. Physically, this can be interpreted as under these conditions there is no preference for anions or cations in the dissolution reaction. In other words, under these conditions both ions are kinetically equivalent since their rates of removal and deposition act symmetrically.”

Comment [31]: Authors must inform how they have estimated k1 and the value obtained for Gypsium must be careful compared with literature. Deviation between experimental and model data must be quantitative determined, for example, through R2 evaluation. Finally, effect of temperature over estimated k1 values must be considered in text.

Response [31]: Eq. (29) is a straight line with only one parameter, k1. Estimating k1 is possibly the easiest task in all of science, especially for the data given in Figure 5. An R2 is somewhat meaningless in this case.

 Comment [32]: This figure must be modified, as the model requires that r is a funcion of s. Otherwise, value of Ksp must be known, in order to apply the model to the observed data.

Response [32]; The fact S is equal to calcium concentration divided by equilibrium concentration, and the equilibrium concentration of calcium is solution saturated in gypsum is well known, this is a somewhat pedantic request. But I have complied.

 

Comment [33]: Authors must discuss better this pH influence and the critheria they have employed in order to sort ou the desired data.

Response [33]: I have added: “above pH 5”.

Comment [34]: The necessity of this investigation must be made clearer in text. Plot of r as a function of s would not be sufficient in order to graphically evaluate the order?

Response [34]: Respectfully, I don’t think that the reviewer has read the sentence carefully enough. I am not ‘graphically evaluating the order’. What I am doing is confirming that the kinetics are non-linear. To make this clear, I have reworded the section to read: “Generally, the dissolution of sparingly soluble salts has been reported as non-linear, that is, the ‘saturation order’   is greater than one. An example of such a non-linear case is that of magnesite. The dissolution of magnesite, MgCO3, in alkaline solutions at 25°C was studied by Pokrovsky and Schott (1999, who presented data on the rate as a function of the concentration of Mg2+ in solution and the chemical affinity. This data can be trans-formed into rate as function of Mg2+ and CO32- in solution. The influence of pH was minimized by selecting data above pH 5 from their dataset.

The data for the rate of dissolution in solution as a function of the saturation state,  , is given in Figure 6. To confirm that the non-linearity of the data for magnesite is not an artifact of the using the saturation state as the independent variable, the data was also plotted as a function of the saturation ratio,   where the saturation ratio is defined as (Zhang and Nancollas, 1990).   can be inter-preted as a mean concentration. These results are also shown in Figure 6 and demonstrate that the dissolution of magnesite is non-linear with respect both   and  .”

Comment [35]: Software used for regression must be referenced in text.

Response [35]: Excel, I am old school!

Comment [36]: authors could include under parenthesis, the physical meaning of stationary state. Should they mean equilibrium?

Response [36]: I have added “(when  is zero)”. I have also gone back to my discussion of this condition and made sure that it is called the stationary state.

Comment [37]: Authors must include a reference for this affirmation or demonstrate (can be included in SI) that this conclusion really holds.

Response [37]: respectfully, this is basic electrochemistry.

Comment [38]: I suggest that the triangle is removedn and a line with -60 inclination included with a different color from the experimental points.

Response [38]: A triangle like this is often used to represent slope.

Comment [39]: Use red and blue colors for the curves. Red for the cation (r and c+) and blue for the anion (r- and c-).

Response [39]: I am colour blind, red does not work for me or other like me.

Comment [40] Authors must explain why they have not employed the model for a non-stoihiometric case and include a brief discussion in text.

Response [40]: respectfully, I do not understand this comment.

Comment [41]; Include proper references from literature to support these comments. Also, text could be improved.

Response [42]: Text is too long! much o these comments have been already included in earlier sections. Conclusions must be quantitative and objective.

Comment [42]: I have shortened by re-arranging

 

 

 

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript regarding the “The Mechanism of Dissolution of Sparingly Soluble Salts – Application of a Novel Electrochemical Theory” by Frank Crundwell is an interesting read. The model developed by the author has already been introduced in prior articles, but the current manuscript discusses the model in the context of sparingly soluble salts and fits the data from prior researcher into their model – which I feel adds sufficient novelty/discussion that I think is worth sharing openly with the research community.

The main limitation of the article is the fact, as the authors states, that there is limited data on the surface potentials and more experimental work would be required on e.g. the dissolution rates of compounds which then could be fitted onto the model. Ideally of course this paper would have presented some new data as well.

Overall, the manuscript is of good quality and I believe it worthy of publishing.

I could not detect anything of major concern in the manuscript. Here are a few of my minor observations I made as I read the manuscript.

1. Line 50-51: “values vary between linear highly non-linear”, should this be “linear to highly non-linear”?
2. Paragraph on lines 192-203 gives various values but no reference from where these values are.
3. Line 436: typo “programme neds to measure”.

Author Response

Comment [1]: Line 50-51: “values vary between linear highly non-linear”, should this be “linear to highly non-linear”?

Response [1]: thank you, changed.

Comment [2]: Paragraph on lines 192-203 gives various values but no reference from where these values are.

Response [2]: These are common to many systems in aqueous solutions. Added references

Comment [3]: Line 436: typo “programme neds to measure”.

Response [3]: Thanks, changed

Reviewer 3 Report

Comments and Suggestions for Authors

The dissolution of sparingly soluble salts is a rather complex physicochemical process associated with the action of a solvent and obeys the general laws of thermodynamics and chemical kinetics it is known. However, elucidating the precise mechanism requires the application of new, unconventional approaches. The application of electrochemical concepts to describing the mechanism of salt dissolution, particularly of sparingly soluble salts, is an interesting problem, so this work is worthwhile.

There are questions and comments regarding the text of the article.

1. Equations (16) and (17) are essentially slow-discharge equations, similar to the Tafel equation. However, how should the potential difference across the Helmholtz layer be written? Is it an outer or an inner layer? The outer layer is in contact with the bulk of the solution, while the inner layer creates a diffuse layer.
2. "The rate of removal of anions and cations from the surface into the solution is an electrochemical reaction of ion transport, dependent on the potential difference at the phase boundary." An electrochemical reaction is a charge transfer that depends on the electrochemical potential of the electrode. Ion transfer is a transport reaction and depends on the electric potential.
3. What was meant by the concept of "surface potential"? Surface potential is the transfer of charge from a phase to the surface.
4. Linear kinetics occurs when the rate of a process is limited by diffusion. Generally, the rate is controlled by various slow stages, which can be observed, for example, by studying the activation energy (Table 1).
5. The assertion that fluorides are removed while cations remain on the surface is very strange; the law of electroneutrality is always observed in solution.
6. As a suggestion (since electrochemistry is involved), it is probably necessary to consider the developments in electrochemical kinetics, for example, by studying the dissolution of salt on a rotating disk and examining the results using the Koutecky-Levich equation, or by considering the dissolution of metals in water to form hydrates, etc.

Author Response

Comment [1]: Equations (16) and (17) are essentially slow-discharge equations, similar to the Tafel equation. However, how should the potential difference across the Helmholtz layer be written? Is it an outer or an inner layer? The outer layer is in contact with the bulk of the solution, while the inner layer creates a diffuse layer.

Response [1]: Respectfully, I don't think I understand your question. The interfacial potential difference was addressed in lines 206 onwards in the original and lines 236 in the revised version. The majority of the potential difference is between the solid and the OHP. Much like the treatment in the mixed potential model of dissolution (see my work on pyrite, for example, where we measured the potential difference), there doesn't seem to be any need to account for the diffuse layer (between bulk solution and OHP).  

Comment [2]: "The rate of removal of anions and cations from the surface into the solution is an electrochemical reaction of ion transport, dependent on the potential difference at the phase boundary." An electrochemical reaction is a charge transfer that depends on the electrochemical potential of the electrode. Ion transfer is a transport reaction and depends on the electric potential.

Response [2]: Respectfully, I am not sure that you are correct. Ion transfer is not transport, that is, "ionic transport" or "ionic migration" (see Bockris and Reddy, 1970). Ion transfer is the electrochemical reaction in which charge transfer of ions occurs, possibly with electrons, but not necessarily (for example, in the anodic dissolution of a metal M ->M+ + e-, only ions cross the interface while electrons remain in the metal). See also Fawcett On the nature of the transfer coefficient for ion transfer reactions J Electroanal Chem 250 1988 225; Koper Schmickler A Kramers reaction rate theory for electrochemical ion transfer reactions Chem Physics 211 1996 123 etc. 

Comment [3]: What was meant by the concept of "surface potential"? Surface potential is the transfer of charge from a phase to the surface.

Response [3]: I am illustrating that in Figure 4.

Comment [4]: Linear kinetics occurs when the rate of a process is limited by diffusion. Generally, the rate is controlled by various slow stages, which can be observed, for example, by studying the activation energy (Table 1).

Response [4]: respectfully, linear kinetics is not only observed in the case of diffusional control. The data I have chosen to model was determined by those authors, and in the case of gypsum, by independent assessment, to be surface reaction controlled. 

Comment [5] The assertion that fluorides are removed while cations remain on the surface is very strange; the law of electroneutrality is always observed in solution.

Response [5] Respectfully, I think that you have got this wrong. Electroneutrality is observed in the bulk of the solution. If only fluorides leave the surface, then the surface is positively charged, and across the interface at the OHP is an excess of negative ions. 

Comment [6]: As a suggestion (since electrochemistry is involved), it is probably necessary to consider the developments in electrochemical kinetics, for example, by studying the dissolution of salt on a rotating disk and examining the results using the Koutecky-Levich equation, or by considering the dissolution of metals in water to form hydrates, etc.

Response [6]: Precisely how some of this data that I have modelled was obtained.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

I thank you once again for reading your work, which is in a much better format than the previous version. However, some improvements must still be performed so that the paper can be published in the journal. Please, refer to the comments in the attached pdf file.

Best Regards.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

  

Author Response

Comment [1] are

Response [1] changed

Comment [2] electrical potential

Response [2] changed

Comment [3] authors must justify the assumptions included in order to arive ta the conclusions about the vacancy concentration at the surface of the dissolving particle.

Response [3] The values for capacitance are easily verified in zeta potential texts and in my own fitting work. I have added the reference to that.  The values for the surface concentration of atoms are based on the size of the atoms or ions. This ranges for atom on structure but is within the range I have given. The rest is a calculation. Incidentally, the same calculation applies to electronic charge in electrochemistry, and the conclusion is the same – the charge is relatively sparse. These are very simple calculations that are easily verifiable. Few people bother, but similar calculations are done in understanding donor and acceptor concentrations in semiconductor physics.

To address the reviewer’s comments, I have made some changes and added a new reference. The paragraph now reads:

“The uncompensated charge on the surface results in a potential difference across the solid-solution interface and the formation of electrified double layer. The measured membrane potentials given in Figures 1 and 2 are in the range of tens to hundreds of millivolts. The interfacial capacitance is typically found to be in the range of 0.01 to 0.2 F/m2  [36]. A reasonable value might be 0.05 F/m2. A change in the potential difference at the surface of 0.1 V corresponds to an increase in the charge of 0.1 V × 0.05 F/m2 = 0.005 C/m2 [44]. This increase in charge is correspondingly caused by an increase in the concentration of anion vacancies, say, over cation vacancies of (0.005 C/m2)/(96 500 C/mol) = 5.2 × 10^−8 mol/m2 or about 10^14 ions/m2, assuming a single charge on each of the vacancies. Since the total surface concentration of constituent ions of the salt is between 10^-3 and 10^-4 mol/m2 (10^19 or 10^20 ions/m2) based on the range of ionic radius [46], the vacancy concentration is several orders of magnitude lower than the total surface concentration. [For an ion of radius 0.5 Å the surface area per mol of surface ions is 1/(0.5 Å × 0.5 Å × 6.02 ×10^23 ions/mol)  = 6.4×10^-4 ions.m2]. Thus, a very low concentration of surface vacancies, 1 in approximately 10^4, has a significant impact on the interfacial potential difference.”

 

Comment [4] Refference format must be checked in the entire doccument. Numbers or Names and year of publication.

Response [4] Updated.

Comment [5] Format of all references  must be checked.

Response [5] Done

Comment [6]  Authors should explain in text what is meant by potential-determining ions and its relation to the nature of Eq. (19). This is link is missing and could contribute considerably to text understanding.

Response [6] I have changed to:

 

Eq. (19) indicates that the potential is dependent on the concentrations of  and  during dissolution or crystallization [35, 36]. In other words, they are potential-determining ions.

 

Comment [7] Include in text a briefly explanation of how from Eq. 22 and 23, equation 24 can be constructed.

Response [7] Changed to

At conditions far from equilibrium the concentrations of and   are small. Setting the terms in Eq. (22) that contain these concentrations to zero Eq. (22) yields the limiting form given by Eq. (24).

 

Comment [8] Authors should consider the inclusiong of a brief discussion of the physical foundations, which lie behind this strong assumption.

Response [8] This is not a strong assumption, it is a mathematical treatment.

Comment [9] I believe that k-1 should be indeed k1. Consider revising the mathemathical form of Eq. 25.

Response [9] Respectfully, the reviewer is mistaken. This is the reverse rate, describing crystal growth.

Comment [10] Authors should justify in text this assumption through plausible physical arguments. It appears to me that they have considered it in order to arive at a specific mathemathical for of Eq. 26.

Response [10] Respectfully, the reviewer is making an assumption that I am trying to force a result. This is not so, as is clear from later on the paper where I describe the dissolution of magnesite. I have made it clear here that the examine this possibility as a mathematical hypothesis. The justification is in the data. Also I am not saying that this hypothesis is always obeyed. Somehow the reviewer is reading more into this than has been said.

Comment [11]  The k1 values and associated R2 values must be presented either in a table or inside the figure.

Response [11] So you want the R2 of a one-parameter linear model to data that is obviously linear? I have put them in the Figure, but quite honestly, this is why people hate statistics. What are you trying to say, that the line is not a fit of the data?

Comment [12] Authors must briefly explain why bellow pH 5 its influence over solubility data should be considered.

Response (12) Change this to:

The rate of dissolution of magnesite is dependent on pH below pH 5 whereas above this value is not a direct influence. Because we wish to test this model without the additional factor pH, data above pH 5 was selected from their dataset .

Comment [13]  These equations are very difficult to read. Consider including them as separated equations and not inside the text and also with a bigger font size.

Response (13)  I have change them a bit.

 

Comment [14] confirm the sign of this derivative. Should it nos be negative (-60)?

Response (14) Correct, and changed

Comment (15)  Model parameters used for constructing Fig. 11 and 12 must be presented ans discussed in text.

Response (15) Figures 11 and 12 are quite clearly illustrationss, and not attempting to fit any one particular set of data or situations. The isn’t even a scale on the figures.

Comment (16) A proper reference must be included in order to corroborate this afirmation.

Response (16) reference added.

Reviewer 3 Report

Comments and Suggestions for Authors

1. Equations (16) and (17) are, in appearance, equations for the polarization curve of a slow discharge. However, it should be kept in mind that these equations include overvoltage as the potential difference between the equilibrium and polarized electrodes, not the potential difference across the Helmholtz layer. The polarization curve shows the dependence of the electrochemical reaction rate on overvoltage, so the article requires a clearer applicability of the dissolution rate to the potential difference across the Helmholtz layer. (Klaus J. Vetter “Ekectrochemical Kinetics”), (Fumio Hide “Electrode Processes and Electrochemical Engineering”).

 

2. The author is mistaken in assuming, for example, in the anodic dissolution of a metal, only ions cross the interface while electrons remain in the metal. Electrons do not remain in the metal but always participate in the cathodic process.

 

3. Fig. 4 shows the removal of a cation or anion from the ionic crystal lattice without taking into account adsorption, hydration, etc. This is more an illustration of the emergence of ionic potential, rather than surface potential.

 

4. The kinetics and mechanism of processes always include the determination of the rate-limiting (slow) stage, which is key to the application of new insights, including electrochemical approaches.

 

5. When reading the article, there is confusion between the formation of an electrical double layer and the electroneutrality of the solution. The electrode surface has a charge that is compensated by its diffuse portion.

 

6. It seems that an electrochemical hypothesis has been proposed based on analogies, observations, and guiding considerations. It is based on a formal application of the slow-discharge theory, but unfortunately, it lacks serious experimental evidence. I propose publishing this article as a discussion piece.

 

Author Response

Comment: Equations (16) and (17) are, in appearance, equations for the polarization curve of a slow discharge. However, it should be kept in mind that these equations include overvoltage as the potential difference between the equilibrium and polarized electrodes, not the potential difference across the Helmholtz layer. The polarization curve shows the dependence of the electrochemical reaction rate on overvoltage, so the article requires a clearer applicability of the dissolution rate to the potential difference across the Helmholtz layer. (Klaus J. Vetter “Ekectrochemical Kinetics”), (Fumio Hide “Electrode Processes and Electrochemical Engineering”).

Reply: The reviewer is mistaken in his/her formulation of the electrochemical rate equation. There is no overvoltage in this expression. The overvoltage is the difference between the potential difference and the potential difference at equilibrium. The reviewer is referred to Eq. 2.39 in Vetter, which is the equation I am using, from which the expression 2.40 is derived in terms of the overvoltage.

 

Comment: The author is mistaken in assuming, for example, in the anodic dissolution of a metal, only ions cross the interface while electrons remain in the metal. Electrons do not remain in the metal but always participate in the cathodic process.

Reply: The reviewer is mistaken in his/her assumption that this is about anodic dissolution. The ions are already formed in the solid. There is no electron transfer, only ion transfer.

 

Comment: Fig. 4 shows the removal of a cation or anion from the ionic crystal lattice without taking into account adsorption, hydration, etc. This is more an illustration of the emergence of ionic potential, rather than surface potential.

Reply: That is correct. I am arguing that the surface is charged due ionic vacancies, as did Grimley and Mott, back in 1950.

 

Comment: The kinetics and mechanism of processes always include the determination of the rate-limiting (slow) stage, which is key to the application of new insights, including electrochemical approaches.

Reply: I don’t understand this comment.

 

Comment: When reading the article, there is confusion between the formation of an electrical double layer and the electroneutrality of the solution. The electrode surface has a charge that is compensated by its diffuse portion.

Reply: I disagree, the surface has a charge that is compentsated by the Helmholtz layer, not the diffuse layer. I made that clear.

Comment: It seems that an electrochemical hypothesis has been proposed based on analogies, observations, and guiding considerations. It is based on a formal application of the slow-discharge theory, but unfortunately, it lacks serious experimental evidence. I propose publishing this article as a discussion piece.

reply: I reject this suggestion.

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

The author proposes a hypothesis based on analogies, observations, and assumptions.

It is based on the formal application of the equations of electrochemical kinetics of electron transfer to a depolarizer. These equations describe the dependence of electric current  on the electrode potential.

In the presented manuscript, these equations are used to describe the dissolution of substances without proper argumentation and without taking into account functional dependencies.

Unfortunately, this hypothesis lacks theoretical justification and experimental evidence.

Author Response

The author proposes a hypothesis based on analogies, observations, and assumptions.

Comments [1] It is based on the formal application of the equations of electrochemical kinetics of electron transfer to a depolarizer. These equations describe the dependence of electric current  on the electrode potential.

In the presented manuscript, these equations are used to describe the dissolution of substances without proper argumentation and without taking into account functional dependencies.

Unfortunately, this hypothesis lacks theoretical justification and experimental evidence.

 

Response [1]

I have shown that the mechanism that I have proposed describes the dissolution of not just one but a number of different systems. I have argued clearly and carefully what is meant at each step along the way. I have shown that there are limiting forms, and found examples in the literature that are described by these limiting forms.

I cannot respond further.