Question

Name some white phosphorus reactions.

Answer 1

White Phosphorus:

• White Phosphorus (${\mathrm{P}}_4$) is a waxy substance that is colourless, white, or yellow and has a garlic-like odour.
• White Phosphorus is a hazardous chemical formed by the breakdown of Phosphate-containing minerals.
• It occurs in tetrahedral molecules composed of four atoms.

Reactions of White Phosphorus:

• White phosphorus is a strong reducing agent, which reduces ${\mathrm{HNO}}_3$ to ${\mathrm{NO}}_2$
• The reaction proceeds as follows:

$\underset{\mathrm{White}\mathrm{Phosphorus}}{{\mathrm{P}}_4\left(\mathrm{s}\right)}+\underset{\mathrm{Nitric}\mathrm{acid}}{20{\mathrm{HNO}}_3\left(\mathrm{l}\right)}\to \underset{\mathrm{Phosphoric}\mathrm{acid}}{4{\mathrm{H}}_3{\mathrm{PO}}_4\left(\mathrm{l}\right)}+\underset{\mathrm{Nitrogen}\mathrm{dioxide}}{20{\mathrm{NO}}_2\left(\mathrm{g}\right)\uparrow }+\underset{\mathrm{Water}}{4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}$

• White phosphorus spontaneously catches fire in Chlorine forming Phosphorus Trichloride and Phosphorus Pentachloride
• The reactions proceeds as follows:

$\underset{\mathrm{White}\mathrm{phophorus}}{{\mathrm{P}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Chlorine}}{6{\mathrm{Cl}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Phosphorus}\mathrm{Trichloride}}{4{\mathrm{PCl}}_3\left(\mathrm{g}\right)}$

$\underset{\mathrm{White}\mathrm{phophorus}}{{\mathrm{P}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Chlorine}}{10{\mathrm{Cl}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Phosphorus}\mathrm{Pentachloride}}{4{\mathrm{PCl}}_5\left(\mathrm{g}\right)}$

• White phosphorus reacts with metals to form Phosphides.
• The reaction is shown below:

$\underset{\mathrm{White}\mathrm{Phosphorus}}{{\mathrm{P}}_4\left(\mathrm{s}\right)}+\underset{\mathrm{Magnesium}}{6\mathrm{Mg}\left(\mathrm{s}\right)}\to \underset{\mathrm{Magnesium}\mathrm{Phosphide}}{2{\mathrm{Mg}}_3{\mathrm{P}}_2\left(\mathrm{s}\right)}$

• Here, ${\mathrm{P}}_4$ is an oxidizing agent, Magnesium is a reducing agent.