Ans: (c)
185. Gasoline is obtained from crude petroleum by
     (a) fractional distillation
     (b) fractional crystallisation
     (c) sublimation
     (d) evaporation
Ans: (a)
186. Rusting is
     (a) an oxidation process
     (b) a reduction process
     (c) a physical change
     (d) an electro-chemical process
Ans: (d)
187. The foul odour of gasoline is due to
     (a) pyridine
     (b) hydrogen sulphide
     (c) cacodyl
     (d) carbylamines
Ans: (b)
188. Mild steel contains
     (a) iron with very low percentage of carbon
     (b) iron with high percentage of carbon
     (c) iron and chromium
     (d) iron and manganese
Ans: (a)
189. Stainless steel contains steel and
     (a) manganese
     (b) vanadium
     (c) nickel
     (d) chromium
Ans: (d)
190. Invar, used for making pendulums is an alloy of steel with
     (a) tungsten
     (b) nickel
     (c) manganese
     (d) chromium
Ans: (b)
191. The compound of iron used in the manufacture of blue-black ink is
     (a) ferric chloride
     (b) ferric sulphate
     (c) ferric thiocyanate
     (d) ferrous sulphate
Ans: (d)
192. The iron salt used in blue prints is
     (a) ferric sulphate
     (b) ferric oxalate
     (c) ferric nitrate
     (d) ferric chloride