(a)  charcoal
     (b)  bleaching powder
     (c)  chlorine
     (d)  carbolic acid
Ans: (a)
117. Graphite la a good conductor of electricity because
     (a) it is an allotrope of carbon
     (b) it gives CO2 on heating
     (c) it contains free electrons
     (d) it is oxidised to graphitic acid
Ans: (c)
118. Which of the following is a regenerated fibre?
     (a) Terylene
     (b) Rayon
     (c) Nylon
     (d) Silk
Ans: (b)
119. A form of carbon which is a good lubricant is
     (a) diamond
     (b) coke
     (c) graphite
     (d) charcoal
Ans: (c)
120. A substance used as a fire-extinguisher under the trade name of Pyrene is
     (a) carbon dioxide
     (b) chloroform
     (c) carbon tetrachloride
     (d) bleaching powder
Ans: (c)
121. Biogas is obtained during
     (a) decomposition of petrol
     (b) fermentation of animal and plant waste
     (c) destructive distillation of coal
     (d) electrolysis of water
Ans: (b)
122. Which of the following is used in fuel to propel rockets?
     (a) Petrol
     (b) Kerosene
     (c) Hydrazine
     (d) Alcohol
Ans: (c)
123. Coke is a substance obtained
     (a) from coal mines
     (b) when wood is burnt in excess of air
     (c) by heating coal out of contact with air
     (d) by heating wood out to contact with air
Ans: (c)