Sodium is very reactive metal and can cause fire in air .Sodium is stored in kerosene........

because it is reactive
& how?there is explanation in science for ex-when Na reacts in H2O it cahches fire coz h2 gas is released so here also there might be some explaination i want that.
ok i m searching it
thnx for ur interest
Na is vrey reactive metal .Sodium is stored in kerosene........
The alkali metals(here:sodium) when react with oxygen burns readily and is explosive as well.A reason for this is that the alkali metals initially forms alkali peroxides.and they have excess amount of oxygen: 
  Na + O

The peroxide provides energy for combustion and the peroxide gets reduced to the more stable alkali oxide (Na
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