(c) Cobalt sulphate
     (d) Nickel sulphate
Ans: (a)
231. Talc contains which of the following? [NDA 2008]
     (a) Zinc, calcium and oxygen
     (b) Calcium, oxygen and tin
     (c) Magnesium, silicon and oxygen
     (d) Zinc, tin and sulphur
Ans: (c)
232. Which one of the following mixtures is homogeneous? [NDA 2008]
     (a) Starch and sugar
     (b) Methanol and water
     (c) Graphite and charcoal
     (d) Calcium carbonate and calcium bicarbonate
Ans: (b)
233. Which one of the following laws explains the formation of carbon monoxide and carbon dioxide from carbon and
     oxygen? [NDA 2008]
     (a) Law of conservation of mass
     (b) Law of multiple proportions
     (c) Law of reciprocal proportions
     (d) Law of definite proportions
Ans: (b)
234. Which one of the following is the most important characteristic of water to act as a good solvent? [NDA 2008]
     (a) Purity of water
     (b) Ionizing power of water
     (c) Polar nature of water
     (d) Dissolving power of water
Ans: (b)
235. When iron is left exposed in open air, it gets rusted. Which constituent(s) of air is/are responsible for rusting iron? [NDA
          1) Oxygen gas present in air.
          2) Moisture present in air.
          3) Carbon dioxide gas present in air.
     (a) 1 only
     (b) 2 only
     (c) 1 and 2
     (d) 2 and 3
Ans: (c)
236. What is the composition of Nitrolim a chemical fertilizer? [NDA 2008]
     (a) Nitrogen and limestone
     (b) Calcium carbide and nitrogen
     (c) Calcium carbide and carbon
     (d) None of the above
Ans: (b)