(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)
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