Question

1.Why cannot we use water for the fire at petrol pump? What type of temporary arrangements are available there 2.how does the bursting of crackers which contain some phosphorus , sulphur and
Magnesium along with other chemicals pollute our environment

3.which of these will have lower ignition temperature ? A) green leaves or dry leaves b) a piece of paper or a piece of wood

Answer 1

We can not use water on fire caused by petrol because petrol is lighter than water and it will float on it and be spreaded to a large area. Fire extinguisher is used to control these types of fires. I think the answer of the second question is that they release harmful gases that pollute the air. In third part I think that dry leaves and a piece of paper will have lower ignition temperature

Answer 2

1.No,we can't use water for the fire at petrol pump because
density of petrol is less than that of water because of which the petrol get spread due to which the fire may also gets spread.So, for extinguishing the fire sands and foam extinguishers are used.
2.Because when the mixture of chemicals and some explosive elements get burnt , releases excess carbon dioxide , carbon monoxide which is a highly poisonous gas and harmful solid residue,which harms our environment.
3.A - dry leaves because they have no moisture.
B-a piece of paper due to it's less thickness and if the block has moisture then the case A may also works on it.