白磷和红磷是磷单质中最常见的两种同素异形体，它们在一定条件下可以相互转化。高中化学（必修加选修）第二册中，在第一章《氮族元素》里讲到了磷。其中有一个演示实验为：红磷加热至４１６℃时升华冷凝转化为白磷。按照教材中的实验步骤：在长玻璃管的中部放少量红磷，玻璃 White phosphorus and red phosphorus are the two most common allotropes of phosphorus, which can be converted to each other under certain conditions. In the second volume of High School Chemistry (Challenge plus elective), phosphorus is described in Chapter 1, Nitrogen Elements. One of the demonstration experiments was: Sublimation condensation of red phosphorus into white phosphorus when heated to 416 °C. According to the experimental procedure in the textbook: Put a small amount of red phosphorus, glass in the middle of the long glass tube