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Q.
White phosphorus catches fire in air to produce dense
white fumes. This is due to the formation of
KVPYKVPY 2017The p-Block Elements
Solution:
White phosphorus is highly reactive and catches fire when exposed to air and produces white dense fumes of phosphorus oxide,
$P_{4}O_{10}$.
$P_{4} + 5O_{2}\rightarrow P_{4}O_{10}$