Question

It is dangerous to cut a piece of yellow phosphorus in air. This is because :

• A. it is poisonous
• B. it gives off fumes
• C. it may catch fire
• D. it explodes in contact with air

Answer 1

The correct option is C it may catch fire

Option C is correct.

Yellow phosphorus (also referred to as white phosphorus), is least stable, most reactive,most volatile, least dense, and the most toxic of the allotropes. When exposed to oxygen, white phosphorus glows in the dark with a very faint tinge of green and blue. It is highly flammable and pyrophoric (self-igniting) upon contact with air. It is poisonous and causes damage to gastrointestinal, hepatic, cardiovascular, and renal systems.

The burning of phosphorus depends on the amount of oxygen available.

$P_4+3O_2\to P_4{O}_6$

$P_4+5O_2\to P_4{O}_{10}$