21 public questions tagged with this topic.
Cyclopentane (C₅H₁₀) requires 15/2 O₂ (C₅H₁₀ + 15/2 O₂ -> 5CO₂ + 5H₂O), less than pentane’s 8 O₂.
Ref: NCERT Class 11 Chemistry > Chapter 9: Hydrocarbons > Topic: Alkanes - Properties - Conformations and Reactions
In superoxides, O has an oxidation number of -1/2. For KO₂: K = +1, so +1 + 2x = 0, 2x = -1, x = -1/2.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
In peroxides, O has an oxidation number of -1. For H₂O₂: 2(+1) + 2x = 0, 2x = -2, x = -1.
Ref: NCERT Class 11 Chemistry > Chapter 7: Redox Reactions > Topic: Classical and Electronic Concept of Redox and Oxidation Number
Initial: PSO₃ = (1 × 0.0831 × 900/1) = 74.79 bar . Let 2x mol of SO₃ dissociate, so PSO₃ = 74.79(1 - 2x) , PSO₂ = 74.79 × 2x , PO₂ = 74.79x , total pressure = 74.79. Kp = ((PSO₂)² PO₂/(PSO₃)²) = ((74.79 × 2x)² (74.79x)/[74.79(1 - 2x)]²) = 0.01 . Simplifying, (4x² · 74.79x/(1 - 2x)²) = 0.01 , 299.16x³ = 0.01 (1 - 2x)² . Solving, x ≈ 0.013 , PO₂ = 74.79 × 0.013 ≈ 0.972 bar .
Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Physical Equilibrium - Solid-Liquid Gas-Liquid and Henry's Law
Initial: [SO₃] = 0.2 M , [SO₂] = [O₂] = 0 . Let x = [O₂] , [SO₂] = 2x , [SO₃] = 0.2 - 2x . Kc = ([SO₂]²[O₂]/[SO₃]²) = ((2x)² x/(0.2 - 2x)²) = 0.02 , 4x³ = 0.02 (0.04 - 0.8x + 4x²) , x ≈ 0.016 M .
Ref: NCERT Class 11 Chemistry > Chapter 6: Equilibrium > Topic: Physical Equilibrium - Solid-Liquid Gas-Liquid and Henry's Law
For O₂(g) → 2O(g), Δ H = 498 kJ/mol. Δ Hf (O₂) = 0, so Δ H = 2 × Δ Hf (O) - 0, Δ Hf (O) = 498 / 2 = 249 kJ/mol.
Ref: NCERT Class 11 Chemistry > Chapter 5: Thermodynamics > Topic: Bond Enthalpy and Entropy and Spontaneity
In H₂O , oxygen has four electron pairs (two bonding, two lone), requiring sp³ hybridization.
Ref: NCERT Class 11 Chemistry > Chapter 4: Chemical Bonding and Molecular Structure > Topic: Valence Bond Theory and Hybridisation - sp sp2 sp3 dsp2
Ge (group 14, valence 4) forms GeO₂ with oxygen (valence 2), a stable covalent oxide, unlike GeO, Ge₂O, or GeO₄.
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Genesis of Periodic Classification - Dobereiner Newlands Mendeleev
Al (group 13, valence 3) and O (group 16, valence 2) form Al₂O₃ by cross-multiplying valences.
Ref: NCERT Class 11 Chemistry > Chapter 3: Classification of Elements and Periodicity in Properties > Topic: Electron Gain Enthalpy and Electronegativity and Valency
For 100 g: C = 26.67 g, H = 2.22 g, O = 71.11 g. Moles: C ≈ 2.22, H = 2.22, O ≈ 4.44. Ratio = 1 : 1 : 2; empirical formula = CHO₂, mass = 45 g/mol. n = 90/45 = 2; molecular formula = C₂H₂O₄.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Mole Concept and Molar Masses and Percentage Composition
Reaction: 2H₂ + O₂ → 2H₂O. Moles: H₂ = 2.5 mol, O₂ = 1.25 mol. 1.25 mol O₂ limits, reacts with 2.5 mol H₂. 2.5 mol H₂O formed = 2.5 × 18 = 45 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Laws of Chemical Combination - Conservation Mass Definite Multiple
Reaction: C + O₂ → CO₂. Moles of CO₂ = 1 mol; requires 1 mol O₂ (32 g). Since 80% reacts, total O₂ = 32 / 0.8 = 40 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
