Why is water not suitable for putting out a petrol fire ? (1) The oxygen content of water is isolated by petrol and thus it helps in burning (2) Petrol is too inflammable to be extinguished by water (3) The heat required for combustion of petrol is very low (4) Water, being heavy, slips below petrol which thus remains in contact with air and burns 

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Answer :

Water, being heavy, slips below petrol which thus remains in contact with air and burns

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Last Answer : (4) Water, being heavy, slips below petrol which thus remains in contact with air and burns Explanation: Water is not effective on petrol fire because it has higher density than ... while petrol stays afloat and keeps burning. Petrochemical fires are nearly always extinguished with chemical foam.

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