Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
ELECTROCHEMICAL CELLS
Galvanic and electrolytic cells:
The difference between potential of the two metals results in a potential difference (also called a electromotive force or voltage, emf) between the two half-cells. That can be measured by means of a high impedance voltmeter which measures the driving force or voltage for reaction without allowing current to flow from which can be calculated thermodynamic data. Alternatively the reaction can be allowed to proceed by connecting the two half-cells by circuit (a wire or a resistor) and allowing the current to flow. These are both examples of galvanic cells, where the chemical reaction occurs. Electrons flow from the electrode with the most negative potential (the anode, where oxidation occurs) to that with the most positive potential (the cathode, where reduction occurs). The salt bridge (or porous glass frit) allows ions to transfer into each half-cell. That flow counteracts the imbalance of charge that would develop in each half cell as electrons (e-) pass from one electrode to the other, which would inhibit the reaction. The need for a frit or salt bridge is avoided if both half cells can share a common electrolyte. It is a special case, where all redox active ions in the solution react at one half cell electrode only and therefore do not have to be separated from the other electrode.
Fig. 1. Examples of (a) an electrolytic cell incorporating a salt bridge; (b) a galvanic cell incorporating a porous frit.
Other half-cell reactions:
The metal-insoluble salt electrode consists of a metal M coated with a porous insoluble salt MX in a solution of X-. A good example is the silver/silver chloride electrode (Fig. 2a) for which the half-cell reaction is, where the reduction of solid silver chloride produces solid silver and releases chloride ion into solution.
Fig. 2. (a) The silver/silver chloride half-cell; (b) the ferric (Fe3+)/ferrous (Fe2+) half-cell; (c) the
fluorine/fluoride ion half-cell.
uses of laboratory apparatus
Q. Why we use Boron? Boron is used to increase the hardness of steels. Crystalline boron is used in transistors. Boron is a good neutron absorber and is used as shields and con
Q. Detect the presence of synthetic food colours in the given samples? Objectives After conducting this activity, you will be able to: • describe the kind of natural
CONVERT 28MG/LTR SODIUM HYDROXIDE INTO MILLI EQUVALENT
Ask question #MinimName two compound that are covalent when taken pure but produce ions when dissolved in water. um00 words accepted#
Q. Test for hydrocyanic acid? Hydrocyanic acid is present as an impurity in synthetic ethyl isothiocyanate, which is employed to make the flavour of mustard oil more pungent. T
Potentiometric titration
Field processing Certain processing techniques at the field itself could help to reduce the chances of spoilage of the fresh produce, specially during transportation. Fruits a
Metal ion configurations in high and low spin octahedral complexes(with)table
preparation of iodoform in lab
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd