191. Water gas is a mixture of
(A) Hydrogen and Oxygen
(B) Hydrogen and Carbon monoxide
(C) Water and Air
(D) Steam and Air

192. Chlorine act as a bleaching agent in the presence of
(A) HNO₃
(B) NaOH
(C) HCL
(D) H₂O

193. The chemical formula of magnetic oxide is
(A) Fe₃O₄
(B) Fe₂O₃.H₂O
(C) Fe2O3
(D) FeO

194. Rain water is acidic in nature because air contains
(A) Oxygen
(B) Nitrogen
(C) Carbon dioxide
(D) All of these

195.  Nutrient pollution of water bodies is caused by
(A) pathogens
(B) acid rain
(C) calcium and magnesium
(D) nitrogen and phosphorus

196. The reason of unusual physical properties of water is due to the presence of
(A) Covalent bond
(B) Coordinate covalent Bond
(C) Hydrogen bonding
(D) None of these

197. The density of water is one gram per centimeter cube at
(A) 60 °C
(B) 4 °C
(C) 100 °C
(D) 0 °C

198. The enormous quantity of water present on earth surface acts as giant thermostat due to its high
(A) Density
(B) Boiling Point
(C) Latent heat values
(D) Heat Capacity

(A) 4.01 kj/mol
(B) 5.01 kj/mol
(C) 6.01 kj/mol
(D) 7.01 kj/mol

200.  Dielectric constant of water at 18 °C is
(A) 80
(B) 90
(C) 100
(D) 110