Use the following picture to help you answer the question: What type of reaction is the examples provided below?

Synthesis Decomposition Single-Replacement Double-Replacement Combustion

Zn + 2HCl ⟶ ZnCl₂ + H₂
CH₄ + 2O₂ ⟶ CO₂ + 2H₂O + Heat
2H₂O₂ ⟶ 2H₂O + O₂
Na₂S + CaCl₂ ⟶ CaS + 2NaCl
N₂ + 3H₂ ⟶ 2NH₃

1 answer

Based on the reactions provided, here’s the classification of each reaction type:

  1. Zn + 2HCl ⟶ ZnCl₂ + H₂ - This is a Single-Replacement reaction because zinc (Zn) replaces the hydrogen (H) in hydrochloric acid (HCl).

  2. CH₄ + 2O₂ ⟶ CO₂ + 2H₂O + Heat - This is a Combustion reaction as it involves the burning of methane (CH₄) in oxygen (O₂), resulting in carbon dioxide (CO₂) and water (H₂O), and producing heat.

  3. 2H₂O₂ ⟶ 2H₂O + O₂ - This is a Decomposition reaction as hydrogen peroxide (H₂O₂) breaks down into water (H₂O) and oxygen (O₂).

  4. Na₂S + CaCl₂ ⟶ CaS + 2NaCl - This is a Double-Replacement reaction because the ions in sodium sulfide (Na₂S) and calcium chloride (CaCl₂) switch partners to form calcium sulfide (CaS) and sodium chloride (NaCl).

  5. N₂ + 3H₂ ⟶ 2NH₃ - This is a Synthesis reaction since nitrogen gas (N₂) and hydrogen gas (H₂) combine to form ammonia (NH₃).

Here's a summary of the types of reactions:

  1. Single-Replacement
  2. Combustion
  3. Decomposition
  4. Double-Replacement
  5. Synthesis