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Total mass = 5.85 + 44.15 = 50 g. Mass % = (5.85/50) × 100 = 11.7%.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: C₃H₈ + 5O₂ → 3CO₂ + 4H₂O. Moles of C₃H₈ ≈ 0.2045 mol. 1 mol needs 5 mol O₂; 0.2045 mol needs 1.0225 mol. Volume = 1.0225 × 22.4 ≈ 22.9 L.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Moles of glucose = 12/180 ≈ 0.0667 mol. Mass of water = 48 g = 0.048 kg. Molality = 0.0667 / 0.048 ≈ 1.39 m.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: CuSO₄ + Zn → Cu + ZnSO₄. Moles of Cu = 12.8/64 = 0.2 mol. 1 mol Cu from 1 mol CuSO₄; mass = 0.2 × 159.5 = 31.9 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
M₁V₁ = M₂V₂. 0.5 × 200 = M₂ × 1000. M₂ = (0.5 × 200)/1000 = 0.1 M.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: 2KClO₃ → 2KCl + 3O₂. Moles of O₂ = 0.1 mol. 3 mol O₂ from 2 mol KClO₃; 0.1 mol needs ≈ 0.0667 mol. With 50% efficiency, KClO₃ = 0.0667 / 0.5 ≈ 0.1333 mol; mass ≈ 16.33 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O. Moles of HCl = 2 × 0.05 = 0.1 mol. 0.1 mol HCl needs 0.05 mol CaCO₃ = 0.05 × 100 = 5 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Moles = 3.36/22.4 = 0.15 mol. Molar mass = 4.8/0.15 = 32 g/mol.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: CuSO₄ + Zn → Cu + ZnSO₄. Moles of Cu = 3.2/64 = 0.05 mol. 1 mol Cu from 1 mol CuSO₄; mass = 0.05 × 159.5 ≈ 8 g.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
Reaction: 2C₂H₂ + 5O₂ → 4CO₂ + 2H₂O. Moles of C₂H₂ = 7/26 ≈ 0.2692 mol. 2 mol C₂H₂ produce 4 mol CO₂; 0.2692 mol produce 0.5384 mol. Volume = 0.5384 × 22.4 ≈ 12.06 L.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
2.54 (3 sig figs), 0.0821 (3 sig figs), 0.00123 (3 sig figs). Result ≈ 169.54; limited to 3 sig figs (170).
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Importance and Nature of Chemistry and Properties of Matter
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
