Self-Test A-3.1: The Chemistry of Combustion

Complete Self-Test A-3.1 and check your answers.

1. What is the ignition temperature of natural gas?
   1. 900ºC
   2. 700ºC
   3. 495ºC
   4. 480ºC

    

2. Select the perfect combustion formula for natural gas.
   1. CH₄ + 2O₂ + 8N₂ → CO₂ + 2H₂O + 8N₂ + Heat
   2. CH₄ + 1O₂ + 4N₂ → CO + H₂O + H₂ + 4N₂ + Heat
   3. C₃H₈ + 5O₂ + 20N₂ → 3CO₂ + 4H₂O + 20N₂ + Heat
   4. CH₄ + 2O₂ + 8N₂ + Excess Air → CO₂ + 2H₂O + 8N₂ + Excess Air + Heat

    

3. At high temperatures, nitrogen can bind to form what type of gases?
   1. C
   2. H₂
   3. CO
   4. NOx

    

4. For each unit of propane, how many units of air are required for perfect combustion?
   1. 10
   2. 15
   3. 25
   4. 30

    

5. What is the primary purpose of excess air?
   1. To increase efficiency
   2. To increase premixing
   3. To ensure complete combustion
   4. To cool the flame and decrease NOx production

    

Answer Key: Self-Test A-3.1 is on the next page.