Multiple choice general knowledge science & technology C3H8 Methane Propane Ethanol Methanol Reveal answer Fill a bubble to check yourself B Correct answer Explanation C3H8 is the molecular formula for propane, a three-carbon alkane used as fuel. Methane is CH4, Ethanol is C2H5OH (C2H6O), and Methanol is CH3OH (CH4O). Propane is commonly used in heating and cooking applications.