The branch of chemistry that deals with the study of redox reactions and how they can be applied to generate electricity (in electrochemical cells) and to carry out non-spontaneous reactions using electricity (electrolysis).

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What's a good resource/book on pH measurements?

Most resources on pH and the electrochemistry behind it that I've found are IMHO too superficial. For example, they explain that an electrode with less than 80% slope should be discarded, but not why ...
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13 views

How do i solve this question in Electrochemistry? [on hold]

i have this question in electrochemistry, please help me, much appreciated!
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1answer
13 views

How exactly is energy created by oxidative phosphorylation

I understand how the protons and electrons move around through various carriers, shuttles and proteins...But there's this talk of electrons being in "lower in energy" at the end. What does that mean? ...
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2answers
73 views

Why use a salt bridge at all in an electrochemical cell?

I was reading about electrochemical cells and I really don't understand why a salt bridge is needed. Can't you just combine the solutions? I've found a lot of webpages explaining electrochemical cells ...
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1answer
35 views

Anode and Cathode Understanding

I am very much confused: in the cell (Zn, Cu in $\ce {H2SO4}$), Cu is positively charged and is anode, where in this cell (Zn in $\ce {ZnSO4}$ and Cu in $\ce {CuSO4}$), Cu is positively charged but is ...
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34 views

calculate original oxidation state of vanadium based on titration value [closed]

the oxidation number of vanadium in a complex ion was determined as follows. A 0.013 mol sample of the complex was dissolved in water and the solution was made up to the 100 cm3. A 10 cm3 portion of ...
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1answer
31 views

Formation of O₂, Water, and Electricity from Hydroxide?

The Clark Type Oxygen Electrode converts water, oxygen, and electrons into hydroxide via a hydrogen peroxide intermediate: \[\ce{O2 + 4e^{−} + 2 H_2O -> 4 OH^{−}}\] Which is the sum of: \[ ...
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1answer
22 views

Ionize Hydrogen and Oxygen Gas in Electrolytic Cell?

As is well known, water can be electrolyzed into oxygen and hydrogen gasses. However, all redox reactions can be run in reverse. If I were to electrolyze water in 2 closed containers (in order to trap ...
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16 views

Is reduction potential equivalent to the ease of discharge?

Loosely speaking, is the reduction potential equivalent to the ease of discharge in the context of electrolysis? i.e. is it easier to discharge an ion with a higher reduction potential as opposed to ...
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26 views

Could I settile for galvanized steel over stainless for salt corrosion resistance?

Bear with me, I'll get to the chemistry soon. I have a float tank that I want to attach a skimmer to. Unfortunately, the enclosure is weakened by cutting a hole out of the ABS plastic. The weight ...
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17 views

Reverse electro-plating byproducts

Following this plan, I am wondering what the byproducts of this method are? At the site with the q-tip, the solution turned a bright yellow, with the q-tip turning a dark yellow, almost red. Holding ...
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24 views

related to potential in electrochemistry

I am working with fuel cell and I got a positive value of oxidation reduction potential at anode whether the fuel cell is voltaic type fuel cell it generate current and potential. How it is possible? ...
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2answers
59 views

Anode and Cathode

I am very much confused: in simple voltaic cell ($\ce{Zn,~Cu}$ in $\ce{H2SO4}$), $\ce{Cu}$ is positively charged and is anode, where in Galvanic cell ($\ce{Zn}$ in $\ce{ZnSO4}$ and $\ce{Cu}$ in ...
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11 views

Which causes of quenching increase specifically in electrochemical experiments?

If quenching is seen as a result of running electrochemical experiments on a solution, what kind of processes may be responsible? I'm thinking about UV/Vis spectroscopy, if it makes any difference. ...
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22 views

The feasibility of the electrochemical cell.

This is the question extracted from my country high school level' exam. So it asks to discuss the feasibility of the electrochemical cell to carry out electrolysis of an aqueous solution of sodium ...
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66 views

Why conductivity of electrolyte decreases on dilution, but molar conductivity increases?

I learnt that on dilution of an electrolytic solution, it's conductivity decreases. However, there is an increase in the molar conductivity of the solution. The book explained the reason by comparing ...
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3answers
58 views

Determine if the following change is an oxidation, a reduction, or neither

The following reaction is not a complete reaction. Determine if the change is an oxidation, a reduction, or neither: $$\ce{CrO4^{-2} -> Cr2O7^{-2}}$$ I know that the answer to this ...
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2answers
32 views

How to use salt spray data in real environments?

I want to convert resultant hours of salt spray corrosion test to estimated values in years for real life environments such as marine. In other words, How could I predict the result of real life tests ...
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1answer
70 views

Why does temperature affect cell potential?

The Nernst equation describes the relationship between cell potential and temperature. But why does temperature affect cell potential? My understanding is that the collision model of kinetics is not ...
3
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1answer
31 views

Is the Nernst equation related to ohmic drop?

Let's consider Nernst equation $$E= E^\circ -\frac{2.303\mathcal{R}T}{n\mathcal{F}} \log Q$$ which, once at $298,15~\mathrm{K}$, is the equivalent of $$E= E^\circ - \frac{0.059}{n} \log Q .$$ Does ...
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1answer
53 views

How can Nernst equation apply in this redox reaction?

$$\ce{CuSO4 + Zn \rightarrow ZnSO4 +Cu}$$ what is the cell potential of the voltaic cell with copper and zinc electrodes if the system is at 50 degrees and the solutions are both at 1 mol? How can it ...
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3answers
64 views

Hydrogen fuel cell - why do the H+ ions move through the electrolyte

Consider the following hydrogen fuel cell http://butane.chem.uiuc.edu/pshapley/Enlist/Labs/FuelCellLab/FuelCell.html At the anode, hydrogen is oxidised (losing electrons). My first question is ...
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22 views

How is streaming potential measured?

This paper describes the measurement of streaming potential using a potential divider configuration. However it is unclear where the potential difference is created. From the diagram it appears that ...
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1answer
18 views

An electric potential is generated when a liquid moves with respect to a solid (streaming potential). Is the reverse true?

Streaming potential is an electrochemical phenomenon that a that relates electric currents with the relative movement of solid and liquid phases in contact with each other. So when a liquid moves ...
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1answer
23 views

Double anode in simple cell

What would happen if I kept two copper plates and one zinc plate in solution of dilute sulphuric acid, and joined two copper plates with wires? (The wires would connect to a single wire and be joined ...
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1answer
34 views

What happens when you react pure metals with solutions of salts? [closed]

Copper reacts with silver nitrate solution. It produces silver and a blue solid called copper nitrate, $\ce{Cu(NO3)2}$. On a piece of copper there's a coating of solid silver. ...
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1answer
32 views

How to convert sodium aluminate back to sodium hydroxide?

I had dissolved a bunch of aluminium foil in an aqeous solution of sodium hydroxide. The resulting solution consists mainly of sodium aluminate with very little excess sodium hydroxide. What I want to ...
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1answer
35 views

Why is chloridric acid used in salt bridges?

I've been planning an experiment on how to make galvanic cells and during my research I came across an article in which chloridric acid was used, along with a soluble salt and agar-agar, in salt ...
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1answer
32 views

Entropy - Negligible?

In electrochemistry, the Nernst equation tells us the cell potential for non-standard conditions. I read that the factor $\frac{-RT}{nF}\ln{Q}$ accounts for difference in cell potential due to ...
2
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1answer
35 views

Why don't ions have one equilibrium potential? (Nernst equation)

I know that equilibrium potentials are dependent on the ratio of ion concentrations inside and outside of the cell and temperature. I also know that the equilibrium potential is reached when there is ...
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1answer
48 views

How does Zinc become oxidized when it's not in direct contact with Copper ions in a Galvanic cell?

Whenever Galvanic Cell is explained in textbooks/videos it usually starts by showing that if you put a piece of $\ce{Zn}$ in a $\ce{Cu^{2+}}$ ion solution the $\ce{Zn}$ will become oxidized and ...
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1answer
42 views

Why does the potential difference of a current drop, when silver nitrate is added to deionised water?

Semi-related to Why do some salt ions in solution conduct electricity better than others? After conducting more experiments, using deionised water as an analyte only, I found the potential difference ...
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2answers
57 views

Why is water considered ionic in fuel cells but otherwise covalent?

If water, $\ce{H2O}$ is a covalent compound formed by sharing of electrons, why is it said (in case of fuel cells) that formation of water from hydrogen and oxygen is a redox reaction (transfer of ...
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2answers
54 views

Concentration of hydrochloric acid for electrolysis?

How much hydrochloric acid (maximum) should I use to do electrolysis of water, and how much amount of voltage should I use to get the maximum of hydrogen and oxygen?
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1answer
37 views

The anode and cathode when corrosion happens

Let's say $\ce{Fe}$ reacts with $\ce{Cu^{2+}}$ ions. $\ce{Fe}$ would oxidize and therefore give electrons to $\ce{Cu^{2+}}$so that: $$\ce{Fe-> Fe^{2+} +2e-}$$ $$\ce{Cu^{2+} +2e^- ->Cu}$$ The ...
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1answer
38 views

Does the speed of an ion affect the current that can flow through a solution?

Typically, when a cathode and anode are inserted into a solution that allows current to flow, the ions are moving with a certain kinetic energy. If the ions were to gain kinetic energy (through ...
5
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1answer
79 views

Why are potentials of cells with magnesium electrode always lower than expected?

I have prepared the 1M water solution of magnesium acetate. Then I placed $\ce{Mg}$ and $\ce{Cu}$ electrodes in it. I predict there such reactions take place: $$\ce{Mg-2e^- \rightarrow Mg^{2+}}$$ ...
2
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1answer
157 views

Why do some salt ions in solution conduct electricity better than others?

My experiment involves a potentiometric titration, and I have used $\ce{AgNO3}$ as a titrant and KCl/KI/deionised water only as an analyte. In the image below of my data, the potential difference as ...
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3answers
218 views

Does increasing concentration of copper sulphate decrease or increase its conductivity?

I am a high school student and for my chemistry lab, I did an electrolyis experiment on how the changing concentration of electrolyte (copper sulphate) will change the rate at which the copper is ...
2
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0answers
21 views

Preparing CdSe electrodeposition bath

What is the best way of preparing an aqueous solution containing 5 mM $\ce{CdSO4}$, 1 mM $\ce{SeO2}$, 0.5 M $\ce{Na2SO4}$ and adjusting pH to 3 by adding 0.5 M $\ce{H2SO4}$? What is the ...
2
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1answer
50 views

Cathodic protection of tubes in Shell & Tube Heat Exchanger

Our $\ce{Cl2}$ liquifier is of the following type: It is entirely made of mild steel (shell as well as tubes plus the connecting pipelines). At shell side there is Freon (R-12) with its ...
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1answer
36 views

offset in measuring decomposition potentials

as far as I've understood to measure the decomposition potential of an electrolyte using a galvanic cell we just put two electrodes, connect them to a battery, and vary the external potential till ...
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1answer
41 views

Ion-selective electrodes

Some ion-selective electrodes can be expensive (starting from $500). Is there any relatively inexpensive do-it-yourself alternatives that would still give very accurate results? How does one make an ...
2
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1answer
21 views

Electrode for methanol

Could you advice an electrode for electrophoretic deposition in methanol which won't spoil methanol and also wont be spoiled by methanol. I googled a bit and found that 1 copper, platinum and gold are ...
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1answer
985 views

Why would 1kW power supplies fail around Nitric acid (HNO3) gas?

I experienced a situation where some electrical power supplies (rated over 1kW) were exposed to nitric acid ($\mathrm{HNO_3}$) fumes at roughly 9ppm for half a day; these power supplies intermittently ...
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1answer
216 views

Principle of potentiometric titration

In potentiometric titration between Ascorbic acid and Iodine when we plot the graph between EMF with volume of iodine consumed, we get a sudden decrease in emf at equivalance point,Why? It is also ...
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1answer
56 views

Iodometric titration of copper - standard electrode potentials

Upon inspection of the standard electrode potentials for the half reactions for both $\ce{Cu^2+}$/$\ce{Cu+}$ and $\ce{I2}$/$\ce{2I-}$, it becomes apparent it should be the iodide ions that act as the ...
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1answer
43 views

Sacrificial Anodes and Pit Corrosion

I have a slab of aluminum and one part of the slab will be exposed to a very corrosive environment. If I put a sacrificial anode elsewhere on the slab will the section that is exposed still be ...
2
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1answer
38 views

Is there an isotope effect for diffusion of an ion through a crystal lattice?

Consider the diffusion of natural abundance $\ce{Li^{+}}$ and $\ce{{}^{6}Li^{+}}$ through a crystalline matrix, say a spinel such as $\ce{LiMn2O4}$. The two lithium ions will have the same ionic ...
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1answer
31 views

Unusual color from leaking battery. What happened?

I was removing old batteries from a camera the other day. One of the batteries had leaked something very bright blue. I have seen batteries leak before and typically the colors look a bit like a ...