Ans: (d)
201. Dust particles in the air of large industrial cities are removed by
     (a) Sedimentation
     (b) Electrophoresis
     (c) Tyndall effect
     (d) Brownian movement
Ans: (b)
202. The fertilizer which has the largest percentage of nitrogen is
     (a) urea
     (b) ammonium nitrate
     (c) ammonium sulphate
     (d) calcium cyanamide
Ans: (a)
203. BHC is a
     (a) Rodenticide
     (b) Herbicide
     (c) Pesticide
     (d) Fungicide
Ans: (c)
204. The compound which is both an antiseptic and a disinfectant is
     (a) phenol
     (b) iodoform
     (c) bleaching powder
     (d) blue vitriol
Ans: (a)
205. Bordeaux mixture contains
     (a) copper sulphate and water
     (b) copper sulphate, lime and water
     (c) thio-urea and lime
     (d) copper sulphate and thio-urea
Ans: (b)
206. A common rodenticide is (Rat Poison)
     (a) malathion
     (b) parathion
     (c) zinc phosphide
     (d) diuron
Ans: (c)
207. A compound used both as a fungicide and as a disinfectant is
     (a) chlorine
     (b) carbon monoxide
     (c) sulphur dioxide
     (d) o-cresol
Ans: (c)
208. A substance used both as an explosive and as a germicide is
     (a) phenol
     (b) TNT
     (c) picric acid
     (d) iodoform