Electrochemistry is the branch of physical chemistry concerned with the relationship between electrical potential, as a measurable and quantitative phenomenon, and identifiable chemical change, with either electrical potential as an outcome of a particular chemical change, or vice versa. These reactions involve electrons moving between electrodes via an electronically-conducting phase (typically, but not necessarily, an external electrical circuit such as in electrolessplating), separated by an ionically-conducting and electronically insulating electrolyte (or ionic species in a solution).
When a chemical reaction is effected by a potential difference, as in electrolysis, or if electrical potential results from a chemical reaction as in a battery or fuel cell, it is called an electrochemical reaction. Unlike chemical reactions, in electrochemical reactions electrons (and necessarily resulting ions), are not transferred directly between molecules, but via the aforementioned electronically- and ionically-conducting circuits, respectively. This phenomenon is what distinguishes an electrochemical reaction from a chemical reaction.
What is the different between spontaneous reduction and spontaneous oxidation? For spontaneous reduction you need to have Ecell to be (+), then what about spontaneous oxidation?
Thanks.
The question:
Balance each of the following skeletal equations by using oxidation and reduction half reactions. All the reactions take place in acidic solution. Identify the oxidizing agent and reducing agent in each reaction.
a) Cl2 (g) + S2O32-(aq) --> Cl-(aq)+SO42-(aq)
My answer so...
Hey guys, I just did a lab on electrochem but we haven't started learning this in our lectures so I'm not too confident on it. One of the lab question asks us to calculate the expected cell voltage. From reading the textbook, this is what I did:
The reaction was 2Ag+ + Cu -> 2Ag + Cu2+
I added...
I conduct an experiment to find the emf of the copper-zinc system . I connect the copper to the positive
terminal of the batery and a potentiometer and the zinc plate to the galvanometer.The galvanometer is connected
to a jockey . The battery I use is 3V .I touch the jockey to the...
what mass of copper could be electroplated on the cathode in an experiment where an average of 200 mA was passed through the cell for 35 mins?
I don't understand the question? how do you figure the mass out? I know that copper is 63.55g/mole but do i mutiple it by 200mA and 35 mins?
hey i seem to be having a lot of trouble qith this question may i get some help?
The standard potential of the cell below is + 0.9509 V at 25 oC. Calculate the solubility, normally called s, of AgI (Note: Enter the natural log of s (ln s) as your answer)
Ag|AgI(s)|AgI(aq)|Ag
i'm using nernst...
I would like to do some research on electrochemistry, seeing as I'm doing a project on PEM Fuel Cells, but where should I start? Do you know any good books? Websites? Contacts?
Thanks, Pierre.o:) :smile:
Hello all,
As I am preparing for my PhD proficiency exam, I tried to solve some Analytical chemistry problems. and stuck in one.
Well, I have attempted to solve this, but have not found enough evidence to study on and solve the problem. What I've done is basicly the following:
I am in...
Hi people, I have the following question. Fe2+, Fe3+, Cr2O7(2-) and Cr3+ are contained in a solution in standard states with dilute sulphuric acid. Deduce what happens. I am wondering here what effect the sulphuric acid has, is it simply a catalyst for the reaction in which the Cr2O72- is...