Problem 49 - Chemistry The Central Science

Question

Write a balanced equation for each of the following reactions: (a) Sulfur dioxide reacts with water. (b) Solid zinc sulfide reacts with hydrochloric acid. (c) Elemental sulfur reacts with sulfite ion to form thiosulfate. (d) Sulfur trioxide is dissolved in sulfuric acid.

Step-by-Step Solution

Answer

(a) \( SO₂ + H₂O \rightarrow H₂SO₃ \) (b) \( ZnS + 2HCl \rightarrow ZnCl₂ + H₂S \) (c) \( 8S₈ + 8SO₃²⁻ \rightarrow 16S₂O₃²⁻ \) (d) \( SO₃ + H₂SO₄ \rightarrow H₂S₂O₇ \)

Step 1: (a) Balancing the Reaction: Sulfur Dioxide with Water

Step 1: Identify reactants and products Sulfur dioxide (SO₂) reacts with water (H₂O). Step 2: Write the unbalanced equation SO₂ + H₂O → H₂SO₃ Step 3: Balance the equation The equation is already balanced: SO₂ + H₂O → H₂SO₃

Step 2: (b) Balancing the Reaction: Solid Zinc Sulfide with Hydrochloric Acid

Step 1: Identify reactants and products Solid zinc sulfide (ZnS) reacts with hydrochloric acid (HCl). Step 2: Write the unbalanced equation ZnS + HCl → ZnCl₂ + H₂S Step 3: Balance the equation ZnS + 2HCl → ZnCl₂ + H₂S

Step 3: (c) Balancing the Reaction: Elemental Sulfur with Sulfite Ion

Step 1: Identify reactants and products Elemental sulfur (S₈) reacts with sulfite ions (SO₃²⁻) to form thiosulfate (S₂O₃²⁻). Step 2: Write the unbalanced equation S₈ + SO₃²⁻ → S₂O₃²⁻ Step 3: Balance the equation 8S₈ + 8SO₃²⁻ → 16S₂O₃²⁻ Note: The coefficients are multiplied by 8 to account for the octasulfur molecule.

Step 4: (d) Balancing the Reaction: Sulfur Trioxide with Sulfuric Acid

Step 1: Identify reactants and products Sulfur trioxide (SO₃) is dissolved in sulfuric acid (H₂SO₄). Step 2: Write the unbalanced equation SO₃ + H₂SO₄ → H₂S₂O₇ Step 3: Balance the equation The equation is already balanced: SO₃ + H₂SO₄ → H₂S₂O₇