Question

Kajal (or) soot is other name for
A.Coke powder
B.Charcoal powder
C.Lampblack
D.None of the above

Answer 1

Hint: We have to ensure that soot is impure carbon particles which are formed from the incomplete combustion reaction of hydrocarbons. It is the result of a certain form of pyrolysis. Soot causes different types of cancer and diseases in lungs.

Complete answer:
We have to know soot is an airborne contaminant in the environment. Soot generally comes in some pattern of pyrolysis. Soot from burning of coal, internal-combustion engines, power-plant boilers, ships boilers, local field burning, fireplaces, furnaces, and forest fires. Soot in low concentration has the tendency to darken surfaces (or) agglomeration of particles. Soot is accountable for the discoloration of the walls found above baseboard electric heating units.
The formation of soot depends on composition of fuel. The order of sooting tendency of components of fuel is naphthalenes-benzenes-aliphatic. Based on the type of flame, the order of shooting of aliphatic varies. Mechanism of soot formation is,
-Soot starts with certain precursors (or) blocks
-Particles are formed by the nucleation of heavy molecules
-Surface growth of particles takes place via adsorption of molecules in gas phase
-Coagulation takes place by collision of particle-particle
-Oxidation of molecules and particles of soot decreases formation of soot
-We can also call soot (or) kajal as lampblack.
Therefore,option (C) is correct.

Note:
We have to know that soot may also form in chimneys in domestic houses possessing one or several fireplaces. Soot is formed in the course of incomplete combustion from molecules of precursor like acetylene. It contains agglomerated nanoparticles with diameters ranging from 6 to 30 nm. The soot particles could be mixed with metal oxides and with minerals and could be coated by sulfuric acid.