Some substances burn on their own when kept exposed in air for some time for example :a)Sulphurb)Oxygenc)Phosphorusd)CarbonCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Phosphorus is a non metal. It catches fire when exposed to air. To prevent the contact of phosphorus with atmospheric oxygen, it is stored in water.

Answer

Phosphorus is burnt when it comes in contact with air....so the correct answer is C...

Answer

Substances that burn on their own when exposed to air:

Sulphur:
- Sulphur is a chemical element that can burn on its own when exposed to air.
- When heated, sulphur reacts with oxygen in the air to form sulphur dioxide gas.
- This reaction is exothermic, meaning it releases heat and light, resulting in the burning of sulphur.
- The burning of sulphur produces a blue flame and a characteristic odor.

Oxygen:
- Oxygen itself is not a substance that burns, but it supports combustion.
- Combustion is a chemical reaction that occurs when a substance reacts with oxygen to produce heat, light, and often flame.
- Oxygen is necessary for most combustion reactions to occur.

Phosphorus:
- Phosphorus is a highly reactive element that can ignite spontaneously when exposed to air.
- It is stored under water or in an inert atmosphere to prevent it from reacting with oxygen in the air.
- When phosphorus comes into contact with oxygen, it undergoes a rapid oxidation reaction, resulting in the release of heat and light.
- This reaction is highly exothermic and can cause the phosphorus to burn with a bright flame.

Carbon:
- Carbon is a non-metallic element that does not burn on its own when exposed to air.
- However, certain forms of carbon, such as charcoal or graphite, can burn in the presence of a flame or a spark.
- When carbon burns, it reacts with oxygen in the air to produce carbon dioxide gas and release heat and light.
- The burning of carbon is a combustion reaction, requiring an external source of ignition.

In conclusion, while sulphur, phosphorus, and certain forms of carbon can burn on their own when exposed to air, oxygen itself is not a substance that burns but supports combustion. These substances undergo exothermic reactions with oxygen, resulting in the release of heat, light, and often flame.

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