Electrochemistry Class 12 Exemplar Solutions

Yeh section Class 12 Chemistry ke important chapter Electrochemistry ke liye NCERT exemplar questions ko lekar hai. In questions se aap concept ki gehrai samajh sakte hain aur apni preparation strong kar sakte hain.

Chapter ke Main Topics

• Galvanic Cells aur EMF
• Nernst Equation aur Applications
• Conductance in Electrolytic Solutions
• Electrolysis aur Faraday ke Laws
• Batteries, Fuel Cells, aur Corrosion

Here we have provided NCERT Exemplar Questionfor Class 12 Chemistry in hindi Language, Just select the chapters below to get Exemplar Solution of the same:

ठोस अवस्था

विलयन

विद्युत रसायन

रासायनिक बलगतिकी

प्रष्ठ रसायन

तत्वो के प्रथक्करण के सामान्य सिधान्न्त एवं प्रक्रम

p ब्लॉक तत्व

ब्लॉक तत्व

उपसहसंयोजन यौगिक

हैलोऐलकेन तथा हैलोऐरीन

ऐल्कोहॉल, फीनौल एवं ईथर

ऐल्डिहाइड, कीटोन एवं कार्बोकिसलिक अल्म

ऐमीन

जैव अणु

बहुलक

दैनिक जीवन मे रसायन

परिशिष्ट

Electrochemistry: Important Exemplar Questions aur Solutions

Electrochemistry me physical chemistry aur electrical science ka combination hota hai. Ye Class 12 ka scoring chapter hai. NCERT exemplar problems ko solve karna aapke liye bohut helpful hoga.

Galvanic Cells aur EMF se Related Numerical Problems

Galvanic cells me chemical energy ka electrical energy me conversion hota hai. EMF (Electromotive Force) calculation karna iska main part hai.

• Example Question: Calculate the standard electrode potential for a cell where Zn/Zn2+ (1M) and Cu/Cu2+ (1M) are connected. (Given E° for Zn2+/Zn = -0.76V and for Cu2+/Cu = +0.34V).
• Solution Approach: E°cell = E°cathode - E°anode. Here, cathode is Cu (reduction) and anode is Zn (oxidation). So, E°cell = 0.34V - (-0.76V) = 1.10V.

Aise questions me aapko identify karna hai ki kaunsa electrode cathode hai aur kaunsa anode. Daniel cell iska best example hai.

Nernst Equation ke Applications

Nernst equation ka use non-standard conditions par cell potential calculate karne ke liye hota hai. Iska formula hai: E = E° - (RT/nF) ln Q.

• Example Question: For the cell reaction 2Ag+ + Cd → 2Ag + Cd2+, if concentration of Ag+ is 0.001 M and Cd2+ is 0.1 M, calculate Ecell at 298 K.
• Key Point: Yaha par pehle standard EMF calculate karo, phir reaction quotient (Q) find karo. Q = [Cd2+]/[Ag+]^2. Phir values ko Nernst equation me put karo.

Concentration cells ka concept bhi Nernst equation par based hai. Isme same electrodes ka use hota hai but different concentrations par.

Electrolytic Conductance aur Kohlrausch's Law

Electrolytic solutions ki conductivity molar conductivity se related hoti hai. Kohlrausch's Law of independent migration of ions ka use weak electrolytes ki molar conductivity calculate karne me hota hai.

• Example Question: The molar conductivity of 0.025 mol L-1 methanoic acid is 46.1 S cm2 mol-1. Calculate its degree of dissociation and dissociation constant. (Given λ°(H+) and λ°(HCOO-)).
• Solution Steps: Pehle λ°m(methanoic acid) calculate karo using Kohlrausch's Law. Phir degree of dissociation (α) = λ°m / λ°m. Phir Ka find karne ke liye formula Ka = Cα^2/(1-α) use karo.

Conductivity cell constant (G*) aur cell measurement se related numerical bhi important hain.

Electrolysis aur Faraday ke Laws

Electrolysis me electrical energy se chemical change laaya jaata hai. Faraday ke First Law aur Second Law quantitative calculations ke liye important hain.

• Example Question: How much electricity in terms of Faraday is required to produce 20.0 g of Ca from molten CaCl2?
• Concept: Ca2+ + 2e- → Ca. Means 1 mole (40g) Ca produce karne ke liye 2 Faraday charge chahiye. So, 20g ke liye, charge = (20/40) * 2 = 1 Faraday.

Aise questions me aapko reaction ka half-equation likh ke stoichiometry samajhni hai. Products ka mass, current, aur time se related problems aati hain.

Batteries, Fuel Cells, aur Corrosion

Ye applied electrochemistry ka part hai. NCERT exemplar me is topic se conceptual questions aate hain.

• Example Question: Why is the cell potential of a mercury cell constant during its lifetime?
• Answer: Mercury cell (Button cell) me reactants ki concentration discharge ke doran constant rehti hai kyunki electrolyte paste form me hota hai aur reaction products bhi solid state me hote hain. Isliye EMF constant rehta hai.
• Corrosion: Rusting of iron ka electrochemical mechanism samajhna zaroori hai. Anode par iron ka oxidation (Fe → Fe2+ + 2e-) aur cathode par oxygen ka reduction (O2 + 2H2O + 4e- → 4OH-) hota hai.

Fuel cells, specifically hydrogen-oxygen fuel cell, ki working principle bhi ek common question hai. Inme clean energy produce hoti hai.

Practice ke Liye Tips

Electrochemistry ke numericals regular practice se hi perfect hote hain. Units par dhyan do - Volts, Amperes, Seconds, Faradays, Ohm-1 cm-1, etc. Formulas ko yaad rakho ya derivation samajh lo. Diagrams jaise galvanic cell, electrolytic cell, dry cell, fuel cell ke labelled diagrams banana seekho. CBSE board exams me yeh chapter se numericals aur theoretical dono tarah ke questions aate hain.