Preferential Discharge of ions during Electrolysis
During electrolysis, the cations being positively charged get attracted towards the negatively charged electrode (cathode) and anions being negatively charged get attracted towards the positively charged electrode (anode). If more than one cations or anions reach an electrode, only one of them preferentially gets discharged at one electrode. Thus, there is a choice amongst the ions that will get discharged on an electrode. This is termed the preferential discharge of ions during electrolysis.
During electrolysis of aqueous solutions, if a cation has higher electrode potential (reduction potential) than water (-0.83 V), then it preferentially discharges at the cathode (e.g. electrolysis of copper and silver salts), otherwise, H2 gas is liberated due to reduction of water at the cathode (e.g. Na, K, Ca salts, etc.).
Similarly, if an anion has higher oxidation potential than water (-1.23V), then it preferentially discharges at anode e.g. Br– (-1.09V), I–(-0.53V), etc., otherwise O2 gas is liberated due to oxidation of water at anode e.g. F– (-2.87 V), SO42- (-2.01V), etc.
The order of ease of discharge (oxidation) of certain anions at anode-
F– < SO42- < NO3– < Cl– < Br– < I– < OH–
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How to Crack NEET in First Attempt
Being a doctor has always been one of the most attractive carriers for the students of science especially of the Biology stream. The earnings of MBBS doctors and their status in our society are really attractive but it is not very easy to crack NEET and acquire all these in a moment. However, it becomes rather easier if you prepare with proper planning and your effort is consistent in the proper direction. How to crack NEET in the first attempt? It is one of the most frequently asked questions by NEET aspirants. In fact, there is not a well-set strategy to crack NEET in the first attempt, but it is well established that the best strategy to crack NEET stands on the following four pillars-
(1) Teacher selection
It is the first and the most important criteria to crack NEET. A teacher of academic or below standard can never let you prepare well for NEET. So, you should select the best mentor that can prepare you well for NEET.
(2) Matter selection
For competitive preparation what is not to study is more important than what to study. You should emphasize more on important and relevant topics (hot spots) and practice more on quality study materials rather than being trapped in rubbish materials floating in the market.
Always remember, if your mentor selection is well then he would provide you the best and relevant study materials and therefore, material selection would become automatically well.
In my opinion, you should concentrate on NCERT books that are Encyclopedia of NEET and you should improve your application part by revision and solving practice papers and previous year’s papers within the prescribed time frame again and again.
(3)Time for starting preparation
When to start preparing for NEET? It is one of the most frequently asked questions by NEET aspirants. In my opinion, you should start your preparation from class 11 and should maintain your tempo till the examinations. If you start too early then it would not be easy for you to maintain your pace for a longer time period and it would develop a frustration in you that is very dangerous for you and your preparation.
(4) Hard work
It is the fourth important pillar of your preparation to crack NEET in the First Attempt. You have selected the best mentors who are providing you the best study materials but you are not serious in your preparation but just wasting your time, then not even God can make you selected in NEET. In fact, there is no shortcut to success, except hard work. So, you should maintain consistency in your preparation. The regular study, regular revision, and solving practice problems and previous year’s papers in a specified time frame are the keys to your selection.
Important Tips for Preparation of NEET
- Select a good mentor for all the subjects. Several educational channels and the best mentors of Physics, Chemistry, and Biology are available online at a very affordable cost. You just subscribe one of them for all the subjects and start your online preparation rather than wandering here and there.
- Centralize your study to the NCERT books and one reference book each for Physics, Chemistry, and Biology. Don’t follow too many books otherwise, you would not be able to complete your syllabus. Always remember, different books differ being only nineteen or twenty in text quality, but never differ of being nineteen and twenty-five.
- Follow quality notes of a good mentor for all the subjects. Don’t run behind the brand, but run behind the concise and effective notes of your mentor.
- Make your own capsule notes for revision.
- Maintain consistency and regularity in your preparation.
- Revise the prepared topics regularly. Always remember, revision is not a waste of time but it makes you perfect. Always keep in mind that, “Revision is division” i.e. Revision improves your marks and ultimately your rank in the final selection.
- Solve practice problems and previous year’s papers in the specified time frame. It would help you to finish your paper timely in the final examination.
- Always be confident in your preparation but never be overconfident. Always read the question carefully and then answer. You usually make mistakes in overconfidence and it has to be reduced.
Important Reference Books
(1) Physics- (1) Concept of Physics by H.C. Verma
(2) Modern’s abc of Objective Physics
(2) Chemistry- (1) Dr. O.P. Tandon (GRB Publication)
(2) Modern’s abc of Objective Chemistry
(3) Biology- (1) Biology by Trueman
(2) Modern’s abc of Objective Biology