English: Generation and combustion of phosphine

Phosphine can be obtained by heating yellow phosphorus and sodium hydroxide. For that purpose, in a flask containing concentrated sodium hydroxide solution, small pieces of yellow phosphorus are inserted. The flask is connected with doubly-bent glass tube with a capillary ending inserted in a water filled beaker. When the phosphine is passed trough the glass tube to the water and when it comes in contact with the air, it ignites spontaneously (due to traces of diphosphine, that spontaneously catches fire in air). These reactions can be described by the following chemical equations:

P₄(s) + 3NaOH(aq) + 3H₂O(l) = PH₃(g) + 3NaH₂PO₂(aq) dominant reaction

3P₄(s) +8NaOH(aq) +8H₂O(l) = 2P₂H₄(g) +8NaH₂PO₂(aq) side reaction

The burning of the two phosphines could be described by the chemical equations:

4PH₃(g) + 8О₂(g) = P₄O₁₀(s) + 6H₂O(g)

2P₂H₄(g) + 7O₂(g) = P₄O₁₀(s) + 4H₂O(g)

Performed by the Prof. PhD Miha Bukleski. The planning of the experiment also included the retired Prof. PhD Vladimir Petruševski and the students Mihail Trajkov and Darko Stojčev, Department of Chemistry, FNSM, Ss. Cyril and Methodius University, Skopje, Macedonia.