71) The reason for chlorinating water is
(A) To propagate germs
(B) To add taste
(C) To add minerals
(D) To kill germs
72) Cooling of vapors of some compounds change them directly into solid state. This phenomenon is called
(A) Sublimation
(B) Evaporation
(C) Condensation
(D) Crystallization
73) Carbonated drinks are examples of
(A) Gas in gas
(B) Gas in water
(C) Gas in solid
(D) Solid in liquid
74) Smoke is a solution of
(A) Solid in solid
(B) Solid in liquid
(C) Solid in gas
(D) Gas in gas
75) Fog is an example of
(A) Gas in gas
(B) Gas in liquid
(C) Liquid in gas
(D) Liquid in liquid
76) The common battery used in automobiles is
(A) Iron storage battery
(B) Copper storage battery
(C) Lead storage battery
(D) Silver storage battery
77) Which acid is present in sour milk
(A) Citric acid
(B) Tartaric acid
(C) Lactic acid
(D) Formic acid
78) The water that can produce good lather with soap is known as
(A) Soft water
(B) Hard water
(C) Heavy water
(D) Atomic water
79) Which of the following is/are the purest form of carbon?
(A) Diamond
(B) Graphite
(C) Buckyball
(D) Marble
80) The glitter of diamond is
(A) Because it is transparent
(B) Because it is a non-conductor
(C) Due to its quality of reflecting light
(D) Because of its density