Dear Bincy, if an authority who is preparing the exam paper reads your question, he might actually drop a question or 2 in the exam paper to surprise you:). Was joking. Now, because this is a National Entrance examination where every year on an average 13 lakhs of aspirants appear for a mere 1 lakh seats, the question paper is bound to throw surprises at you. And for 45 questions to be framed out of 30 Chapters from Chemistry, you cannot afford to skip any chapter. Infact, Electrochemistry has been given a weightage of 2% based on previous question papers. That's approximately 4 questions from this Chapter alone. So its better to be safe than to be sorry. Please visit our page to check the weightage  of each Chapter in each subject: https://medicine.careers360.com/articles/neet-chapter-wise-weightage-and-important-topics

Dear Aspirant,

Probability of coming a question directly based on nernst equation is quite low and there is a chance that you might get 180/180 without studying the topic.

However, I would suggest that you should not skip an topic as there might be a very simple question from this topic and then you might regret not studying it. You cannot say for sure which topic come and which not in an exam like NEET.

Hope this helps. Thank You.