Answer : The type of reaction described in the sentence is Synthesis or Combination
Explanation :
The balanced equation for the reaction between Phosphorous and Oxygen gas can be written as
From the above equation we can see that there are two different reactants ( P and O₂ ) which are combining with each other to give a single product.
This type of reaction is known as Combination or Synthesis.
A general form of Synthesis reaction is given below.
Here we can conclude that a synthesis / combination reaction is the one where 2 or more reactants combine together to give only one product .