Question

Which of the following non metals reacts and catches fire on exposure to air

Answer 1

Answer:

Sodium and potassium and phosphor can be catches the fire if exposed to AIR. non-metal which catches fire on reaction with air.

hope it helpfull

Answer 2

Answer:

Phosphorus is a 'non-metal' that 'reacts and catches fire' on exposure to air'.

Explanation:  

When white phosphorus gains 'contact with air', it spontaneously combusts and catches fire. The resultant vapor contains Phosphorus oxide and burns on to create the toxic compound. The element catches fire in air as it is extremely reactive, and to prevent this occurrence is stored underwater. Red phosphorus, on the other hand, is more stable but with heat or sunlight, it too catches fire in the air.