The gas responsible for most of the fatal explosions in coal mines isA. butaneB. etheneC. ethaneD. methane

The main constituent of natural gas isA. HydrogenB. OxygenC. ButaneD. MethaneE. Ethane

Subject: ScienceScenario : Ajay was watching television and saw the news about recurring fire accidents in coal mines.  He searched about the cause of these fire accidents. He found out that this happens due to the spontaneous combustion of coal dust in the mines, as coal dust unexpectedly bursts into flame without requiring any external ignition.He researched more about combustion and found out that it is a chemical process in which a substance reacts with oxygen to give off heat. The combustion process is of three types, as follows. Rapid Combustion Spontaneous combustion Explosive CombustionSubstance burns rapidly. Substance unexpectedly bursts into flame. Substance burns with sudden production of heat, light and sound.It releases a large amount of heat on burning. It releases a small amount of heat on burning. It releases a large amount of heat on burning.It requires an external ignition. No external ignition is required. It requires an external ignition.Example: the combustion of LPG Example: combustion of sodium on exposure to air Example: burning of firecrackers.Question:5 )  Ajay switches on the stove and brings a burning matchstick closer to the stove. Will the burning matchstick light up the stove?A)   Yes, the burning matchstick will light up the stove as the gas burns rapidly on external ignition.B)    No, the burning matchstick will not light up the stove, as the gas does not require any external ignition to burn.C)    No, the burning matchstick will not light up the stove as the gas is not getting any external heat from the matchstick.D)    Yes, the burning matchstick will not light up the stove as the gas burns spontaneously on coming out of the inlets of the stove.NEXT

Which of the following is NOT produced by burning coal?a.CO2b.Ozonec.NOxd.SO2

If methane is burnt in sufficient oxygen the products formed are :A.

What substance is decomposed into CO2 and CaO in the blast furnace?1 markCokeLime stoneCarbonCarbon dioxide