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#chemical reaction

12 public questions tagged with this topic.

For A(g) + 3B(g) 2C(g) , Kp = 0.125 at 600 K. If PA = 1 atm , PB = 2 atm initially, what is PC at equilibrium?

Let PC = 2x , PA = 1 - x , PB = 2 - 3x . Kp = ((PC)²/PA (PB)³) = ((2x)²/(1 - x)(2 - 3x)³) = 0.125 , 4x² = 0.125 (1 - x)(2 - 3x)³ , x ≈ 0.25 , PC = 0.5 atm .

Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Relationship Between Kp Kc and Factors Affecting Equilibrium - Le Chatelier

For 2A(g) + B(g) 2C(g) , Kp = 16 at 500 K. If initial pressures are PA = 2 atm , PB = 1 atm , what is PC at equilibrium?

Let PC = 2x , PA = 2 - 2x , PB = 1 - x , total pressure = 3 - x . Kp = ((PC)²/PA² PB) = ((2x)²/(2 - 2x)² (1 - x)) = 16 , (4x²/4(1 - x)² (1 - x)) = 16 , (x²/(1 - x)³) = 4 , (x/1 - x) = 2 , x = 2 - 2x , 3x = 2 , x = (2/3) , PC = 2 × (2/3) = 1.33 atm .

Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Physical Equilibrium - Solid-Liquid Gas-Liquid and Henry's Law

For the reaction A(g) + 2B(g) 3C(g) , Kc = 27 at 400 K. If 1 mole of A and 3 moles of B are placed in a 1 L vessel, what

Initial: [A] = 1 M , [B] = 3 M , [C] = 0 . Let 3x be moles of C formed, so A decreases by x , B by 2x . At equilibrium: [A] = 1 - x , [B] = 3 - 2x , [C] = 3x . Kc = ([C]³/[A][B]²) = ((3x)³/(1 - x)(3 - 2x)²) = 27 , (27x³/(1 - x)(3 - 2x)²) = 27 , (x³/(1 - x)(3 - 2x)²) = 1 . Solving, x³ = (1 - x)(3 - 2x)² , test x = 0.5 : (0.5)³ = 0.125 , (1 - 0.5)(3 - 1)² = 0.5 × 4 = 2 (not equal). Solving numerically, x ≈ 0.75 , [C] = 3 × 0.75 = 2.25 M .

Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Physical Equilibrium - Solid-Liquid Gas-Liquid and Henry's Law

For H₂(g) + I₂(g) 2HI(g) , Kc = 50 at 700 K. If 0.2 mol H₂ and 0.3 mol I₂ are in a 1 L vessel, what is [HI] at equilibri

Initial: [H₂] = 0.2 M , [I₂] = 0.3 M , [HI] = 0 . Let 2x = [HI] , [H₂] = 0.2 - x , [I₂] = 0.3 - x . Kc = ([HI]²/[H₂][I₂]) = ((2x)²/(0.2 - x)(0.3 - x)) = 50 , 4x² = 50 (0.06 - 0.5x + x²) , 46x² - 25x + 3 = 0 , x ≈ 0.15 , [HI] = 0.3 M .

Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Ionic Equilibrium - Acids Bases and pH and Ionization of Weak Acids Bases