By which process, coal is formed?
WEB(b) Destructive distillation of coal yields (i) coal tar (ii) coal gas (iii) coke (iv) all of the above (c) Lamp black is (i) an amorphous form of carbon (ii) a crystalline form of carbon (iii) a pure form of carbon (iv) a cluster of carbon atoms (d) The process by which decayed plants slowly convert into coal is called (i) petrifiion (ii ...