Question
Question: Compounds used in safety matches is: A.\({{P}_{4}}{{S}_{3}}\) B.\({{P}_{4}}\) C.\({{P}_{2}}{...
Compounds used in safety matches is:
A.P4S3
B.P4
C.P2O5
D.PCl3
Solution
safety matches are the matchsticks that are able to burn without harming other materials. It is due to the presence of burning compounds that are present on the head of the matchstick. On burning the matchstick, the reaction happens with oxygen in the air, and sulfur dioxide gas is released.
Complete answer:
Burning of a matchstick is the most common activity that everyone must have done. These matchsticks are termed as safety match sticks as they consist of a compound that gets burnt in air without burning the stick and other materials. The reaction here happens due to rigorous action of the matchstick with the filler on the match box.
The match stick contains phosphorus sulfide,P4S3, that is rubbed against the match box having a filler or a frictional surface containing red phosphorus. The reaction has phosphorus sulfide reacting with oxygen to produce phosphorus pentoxide. The reaction is a type of exothermic reaction as it produces light and heat. The reaction is as follows:
P4S3(s)+O2(g)→P4O10(s)+SO2(g)
So, the compound used in safety matches is phosphorus sulfide which is P4S3, therefore option A is correct.
Note:
The head of the safety match stick basically has a mixture of potassium chlorate along with phosphorus sulfide and glass binder that keeps them intact. The potassium chlorate acts as an oxidizing agent that gets converted to oxygen that causes the ignition of the phosphorus sulfide and makes it burn with more intensity.