Formation of sulfur colloids
What happens when we pass sulfur vapors through cold water?


You get more or less coarse sulfur powder-slurry. 


  What is the reaction for it?


Sulfur vapor ( S2 mostly) reacts to form S8 
depending on speed of cooling, some S6 might 
form temporarily


  Which type is colloid is this?


Sometimes this might result in a "colloid", 
but I recommend not to use this outdated word, 
because so much nonsense was written in the classical 
days of "colloids".


  And why doesn't it form in hot or lukewarm water


Who says/writes this?