Chemistry
Water is not effective in extinguishing a fire caused by petrol because

The flame is too hot for water to cool it down
Water and petrol are miscible with each other
Water and petrol are immiscible with each other and petrol which forms the upper layer continues to burn
Water and petrol react chemically

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Chemistry
The open "Sigrees" or coal stoves often require fanning to sustain burning because of

Lack of oxygen in the surroundings of sigrees
Interrupted release of moisture from the material
Accumulation of smoke and dust over the sigrees
Tendency of carbon dioxide to form a layer along with dust smoke

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