Properties of Fuel Gases Flashcards
6 cards from real G3 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Properties of Fuel Gases flashcards as text
What happens to natural gas volume when temperature increases at constant pressure?
Answer: Volume increases proportionally (Charles's Law)
Charles's Law: volume increases proportionally with temperature at constant pressure.
Why does natural gas heating value vary between supply regions?
Answer: Composition varies by source with different hydrocarbon proportions
Different geological sources produce gas with varying methane, ethane, and propane proportions.
What is flame rectification in gas appliances?
Answer: Proving flame presence by detecting electrical conductivity of a flame
A flame rod conducts AC current that becomes rectified (DC) by the flame to confirm ignition.
How does propane's flue gas dew point compare to natural gas?
Answer: Propane has a higher dew point (~59°C) than natural gas (~54°C)
Propane produces more water vapour per BTU, giving a higher dew point of about 59°C.
How does altitude affect gas appliance performance?
Answer: Higher altitude means less oxygen, requiring derating
At higher altitudes, reduced air density means less oxygen, requiring input reduction.
How do flammability limits relate to gas leak safety?
Answer: Understanding limits helps determine safe ventilation rates and detector alarm setpoints
Flammable limits inform ventilation rates to keep below LEL and set detector alarms at 10-25% of LEL.