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🔹 Electrochemistry : A branch of science that explores the connection between electrical current and chemical reactions, linking them together. - Looking ahead, 🧪Electrochemical cells are classified into two main types: 🌿🔋Electrolytic cells & ⚗️Galvanic cells. 🔋 Electrolytic Cell 🔋 🔋 Electrolytic cell : - Electrolytic cell is a device which converts : ⚡️Electrical energy(from an external source) ➡️➡️🔋Chemical energy. - An electrolytic cell contains 2 rods, also called electrodes⚗️. 🌿These electrodes can be made of different metals or the same metal, like graphite or metallic ones. They are dipped in the same 🔬electrolytic solution. - The electrode is linked to the battery🔋. 🌿One electrode connected to the positive terminal of the battery is called the Anode (+), marked with a positive sign. 🌿The other electrode connected to the negative terminal of the battery is known as the Cathode (-), bearing a negative sign. ⚡️🔋 ⚗️ Galvanic cell ⚗️ ⚗️ Galvanic cell : - Galvanic cell is a device which converts : 🔋Chemical energy(of a redox reaction) ➡️➡️⚡Electrical energy. - An Galvanic cell contains 2 rods, also called electrodes⚗️. 🌿These electrodes(half cells) are made of different metals and are connected by salt bridge. They are dipped in different electrolytic solution respective 🔬electrolytic solution. - The electrodes are connected to a potentiometer or voltmeter by an electrical wire. ⚡️ - The electrode where oxidation occurs is called : 🌿Anode (Negative (-) Electrode). ⚗️ - The electrode where reduction occurs is called : also spontaneous redox reaction takes place on electrode 🌿Cathode (Positive (+) Electrode). ⚡️ 🌿Example: Daniel cell 🔄 🌊Salt bridge & ⚖️Functions : 🌿 A salt bridge is like an upside-down U-tube filled with a strong electrolyte solution, such as 💡KCl, KNO3, or NH4Cl. 🌿These electrolytes are chosen because the ions move at similar speeds, helping balance charges. ⚖️Function of the Salt Bridge: 🌿Connects🔗 Half-Cells : Joins them to complete the circuit. 🌿Prevents Mixing🚫 : Stops solution movement between half-cells. 🌿Maintains Balance⚖️ : Keeps both halves electrically neutral. 🌿Prevents Potential Differences🛑: Stops liquid junction potential. ⚡️ EMF of a Cell : 🌿When two electrodes connect, current moves from higher potential to lower potential. The difference in potential that drives this current is called the EMF of the cell. 🌿Ecell = E Cathode - E Anode 🌿Here, E cathode and E Anode are the reduction potentials of the cathode and anode, respectively. 🔹 Understanding Electrode Potential: 🌿When a metal meets its electrolytic solution, it picks up a charge, resulting in electrode potential. This reflects the metal's tendency to either lose or gain electrons. ⚡️ Oxidation Potential: Metal's tendency to lose electrons. ⚡️ Reduction Potential: Metal's tendency to gain electrons. 🔹Standard Electrode Potential: 🌿At a specific temp, it's a metal's tendency to oxidize or reduce when in contact with a 1M ion solution. 🌿SRP (Standard Reduction Potential): It's the tendency of a substance to undergo reduction. 🌿SOP (Standard Oxidation Potential): It's the tendency of a substance to undergo reduction. 🌟Thermodynamics of EMF of Cells 🧬Relationship between Enthalpy Change and EMF: 🌿Using the Gibbs-Helmholtz equation: Combining equations (1) and (2): 🔹Nernst Equation & Its Derivation: 🌿The Nernst Equation helps us find cell or electrode potential in non-standard conditions. It connects the measured potential to the reaction quotient. 🔸Deriving the Equation: 🌿Consider a redox reaction: aA + bB → cC + dD .. make this in
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