JAMB - Chemistry (1978 - No. 34)

Two gas cylinders contain ethylene (ethene) and acetylene respectively. One test which can be used to distinguish between them is by?

passing each gas through bromine water

passing each gas through dilute potassium permanganate solution

passing each gas through silver nitrate solution

treating each gas catalytically with excess hydrogen gas

Acetylene reacts with ammoniacal AgNO3 solution to form a white precipitate of silver acetylide (AgC-=Cag) but ethylene does not