Carbon and Fossil Fuels

This is the correct option as charcoal does not burn by producing a flame. It is a solid fuel that does not vapourise on heating. It only glows on combustion.

This option is correct because pyrolysis oil is also known as bio crude or boi oil. It is extracted by bio mass to liquid technology of destructive distillation from dried bio mass in the reactor at the temperature of about 500^oC. It contains a high amount of hydrocarbon.

Gneiss is not a type of coal - it is a metamorphic rock formed from high-grade metamorphism of igneous or sedimentary rocks. Lignite, Anthracite, and Peat are all types or stages of coal formation, with Peat being the lowest grade, Lignite being brown coal, and Anthracite being the highest grade hard coal.

Jatropha has the potential to provide economic benefits at the local level since under suitable management it has the potential to grow in dry marginal non-agricultural lands, thereby allowing villagers and farmers to leverage non-farm land for income generation. Jatropha oil can be used directly after extraction (i.e. without refining) in diesel generators and engines.Jatropha oil is carbon-neutral, large-scale production will improve the country's carbon emissions profile.

A supporter of combustion is a substance that enables or supports burning. Oxygen is essential for combustion as it reacts with fuel during the burning process. Carbon dioxide (CO2) is actually used to extinguish fires by displacing oxygen. Water vapor and sand do not support combustion.

Kerosene oil has the lowest ignition temperature among the options - it vaporizes easily and catches fire at relatively low temperatures (approximately 210°C). Wood requires much higher temperatures (around 300°C), charcoal needs even higher heat, and cooking oil has a higher flash point (around 300-350°C) than kerosene. The ease of vaporization affects ignition temperature.

Carbon dioxide is the best fire extinguisher among these options because it's heavier than air, forms a blanket that displaces oxygen, and doesn't conduct electricity (safe for electrical fires). Water can spread grease fires and conducts electricity. Woollen cloth can smother small fires but is not as effective or versatile as CO2 for general firefighting.

Carbon dioxide (CO2) is heavier than oxygen and air, which allows it to settle and form a blanket over burning material, displacing the oxygen needed for combustion. CO2 does NOT react with oxygen (option A is wrong), and it does NOT raise temperature (option D is wrong). Its effectiveness comes from being denser than oxygen and physically displacing it.

Charcoal does NOT vaporize when burned - it undergoes solid-to-gas combustion where carbon directly reacts with oxygen, producing CO2 without passing through a liquid or vapor phase. Wax, kerosene, and wood all vaporize first (solid/liquid → gas) before burning - the combustion occurs in the gas phase. This is why charcoal leaves ash residue while the others burn away more completely.

Coal combustion produces carbon dioxide (CO₂) from the carbon content, and releases heat and light energy. Hydrogen gas (H₂) is not a direct product of coal burning; the hydrogen in coal combines with oxygen to form water vapor (H₂O), not hydrogen gas.

Combustion can occur in all three states of matter. Solid fuels like wood and coal burn, liquid fuels like petrol and alcohol burn, and gaseous fuels like natural gas and LPG burn. The physical state does not prevent combustion if the ignition temperature is reached.

Inflammable substances have very low ignition temperatures, meaning they can catch fire very easily with minimal heat input. Examples include petrol, alcohol, and LPG. The term 'inflammable' is synonymous with 'highly flammable'.

Wood has a relatively high ignition temperature (around 300°C). A matchstick produces brief, localized heat that is insufficient to raise the wood's temperature to its ignition point before the match extinguishes. Sustained contact or kindling is needed to reach the ignition temperature.

The fire triangle requires three essential components: fuel, oxygen (or an oxidizing agent), and heat. These three must be present for fire to exist. Carbon dioxide is NOT required for fire - in fact, it's used to extinguish fires by displacing oxygen.