Question

Which of the following is used in making smoke bombs?
A.Sulphur
B.Phosphorus
C.Hydrogen
D.Carbon

Answer 1

Hint: Although modern smoke grenades are designed not to directly emit sparks or any fire but they remain a fire hazard and are capable of igniting dry vegetation or flammable substances if used unwisely. White phosphorus burns with a brilliant yellow flame while producing ample amounts of white smoke which is phosphorus pentoxide $({P_4}{O_{10}})$ .

Complete step by step answer:
A smoke bomb is a well-known firework designed to produce smoke when ignited. Smoke bombs are most necessarily used in military units, airsoft games, paintball games, self-defence and pranks. The very first smoke bomb was created by the inventor Robert Yale in 1848. Robert Yale developed 17th century Chinese-style fireworks and later on modified the formula to produce more and more smoke for a longer period of time. The formula that is used by Coloured smoke devices consists of an oxidizer, a fuel generally sugars, potassium chlorate $(KCl{O_3})$ , a moderator, such as sodium bicarbonate $(NaHC{O_3})$ to keep the reaction from getting too hot, and a powdered organic dye. The burning of this mixture evaporates the dye and forces it out of the device, where it condenses in the atmosphere to form a smoke which is finely dispersed particles. A smoke ball is a hollow and cherry-sized sphere of brightly coloured clay filled with a smoke-generating composition that produces a forceful jet of coloured smoke for good 10 to 15 seconds.

Therefore, the correct answer is option (B).

Note: The military uses smokes most probably WP to protect friendly forces, identify enemy targets and tactical locations, support deception operations, and to obscure certain reconnaissance activities, surveillance, and targets from enemy forces.