Question

Why does a matchstick start burning on rubbing it on the side of the match box?

Answer 1

due to reaction of phosphorus

Answer 2

because the modern match stick contain antimony trisulpite and potassium chlorate . the rubbing surface contain has powdered glass and a little red phosphorus when the match stick stricks with the rubbing surface the red phosphorus converted to white phosphrous this immediately reacts with potassium chlorate in the match stick to ignite antimony trisulphide and start the combustion