Yeh notes aapko Electrochemistry ke basic se lekar advanced concepts tak help karenge. NCERT ke according, yahan aapko electrochemical cells, conductance, electrolysis, aur Faraday's laws ke baare mein samajh milti hai.
Electrochemical cells wo devices hote hain jo chemical energy ko electrical energy mein convert karte hain ya uske ulta. Do types hain: Galvanic (Voltaic) cells jo spontaneous reactions se electricity produce karte hain, aur Electrolytic cells jo external electricity ki madad se non-spontaneous reactions karwate hain.
Ek typical galvanic cell mein do half-cells hote hain - anode (oxidation hoti hai) aur cathode (reduction hoti hai). Dono half-cells salt bridge se connected hote hain jo ion flow maintain karta hai. Jaise Daniell cell mein zinc anode aur copper cathode hota hai.
Nernst equation cell potential ko concentration ke saath relate karta hai: E_cell = E°_cell - (RT/nF) ln Q. Standard temperature pe (298K), equation E_cell = E°_cell - (0.0591/n) log Q ban jata hai. Is equation se hum pH aur equilibrium constant bhi nikaal sakte hain.
Electrolytic solutions ki conductance unke ion concentration aur mobility par depend karti hai. Specific conductance (κ) aur molar conductance (Λm) do important terms hain. Molar conductance concentration decrease hone par increase hota hai (Kohlrausch's law).
Kohlrausch ke anusaar, infinite dilution par molar conductance ions ke individual contributions ka sum hota hai: Λ°m = λ°+ + λ°-. Is law ke through weak electrolytes ki dissociation constant calculate ki ja sakti hai.
Faraday ke do laws hote hain. Pehla law: Electrolysis ke dauran deposit ya dissolve hone wale padarth ka mass current aur time ke proportional hota hai (m = ZIt, jahan Z electrochemical equivalent hai). Doosra law: Jab same quantity of charge different electrolytes se guzarti hai to deposit hone wale masses unke chemical equivalents (E) ke ratio mein hote hain.
Batteries multiple galvanic cells ka combination hote hain. Primary batteries (e.g., dry cell) rechargeable nahi hote, jabki secondary batteries (e.g., lead storage battery, Ni-Cd) recharge kiye ja sakte hain. Fuel cells continuous supply of fuel aur oxidant se electricity produce karte hain; hydrogen-oxygen fuel cell ek achha example hai jisme water by-product hota hai.
Corrosion ek electrochemical process hai jisme metal apne compounds mein convert ho jata hai (jaise iron ka rusting). Rusting ke liye oxygen aur moisture ki zaroorat hoti hai. Galvanization (zinc coating) ya cathodic protection se corrosion ko roka ja sakta hai.
Yeh notes aapko Class 12 Chemistry ke Electrochemistry chapter ke liye taiyar karne mein madad karenge. Practice karte rahe aur numerical problems solve karein.
