(a) Steel
     (b) Graphite
     (c) Tungsten
     (d) Diamond
Ans: (d)
135. Which of the following is a non-metal that remains liquid at room- temperature? [NCA 1991]
     (a) Bromine
     (b) Chlorine
     (c) Helium
     (d) Phosphorus
Ans: (a)
136. Which of the following is a non-ferrous metal?
     (a) Aluminium
     (b) Iron
     (c) Nickel
     (d) Cobalt
Ans: (a)
137. Sodium metal is kept under: [BSF 1990]
     (a) water
     (b) alcohol
     (c) petrol
     (d) kerosene
Ans: (d)
138. Which of the following statements about "dry ice" are correct?
         1) It is a useful refrigerant.
         2) On heating, it turns into a liquid.
         3) It has acidic properties.
         4) It causes burns when pressed against the skin.
     (a) 1 and 3
     (b) 1, 2 and 3
     (c) 2 and 4
     (d) 1, 3 and 4
Ans: (a)
139. The metal used in storage batteries is:
     (a) iron
     (b) copper
     (c) lead
     (d) tin
Ans: (c)
140. Water has maximum density at :
     (a) -1°C
     (b) 0°C
     (c) 4°C
     (d) 100°C
Ans: (c)