81. The gas used in packets of chips is:
(A) Carbon dioxide
(B) Nitrogen
(C) Oxygen
(D) Argon
82. The foods with a very high energy source are:
(A) Carbohydrates
(B) Fats
(C) Proteins
(D) Minerals
83. What is cross eyes?
(A) Out of focus eyes
(B) Due to imbalance in ocular muscles eyes turn inward or outward
(C) Weak eyes operated
(D) Eyes which cannot be
84. The smallest unit of a compound is:
(A) Element
(B) Atom
(C) Molecule
(D) Mole
85. Acetic acid is commonly used in household as:
(A) Vinegar
(B) Vitamin C
(C) Lemon juice
(D) Aspirin
86. The chief constituent of natural gas is:
(A) Methane
(B) Ethane
(C) Propane
(D) Chlorine
87. When a hydrogen-filled balloon rises high in the atmosphere:
(A) It will expand
(B) It will shrink in size
(C) Its size will remain unchanged
(D) Will depend on air pressure
88. Mud homes are cooler in summers and warmer in winters as compared to brick houses because:
(A) Mud is a good conductor
(B) Mud is a bad conductor
(C) Mud is a neutral insulator by nature
(D) Cooling in summers and sunlight coming through holes causes warming in winters
89. Water is a highly effective coolant for a car engine because:
(A) Water is a good conductor of heat
(B) Water has very high specific heat capacity
(C) Water boils at a comparatively high temperature
(D) Evaporation of water produces a lot of cooling
90. The ozone layer above Earth’s atmosphere:
(A) Prevents infrared rays’ radiation from the sun reaching Earth
(B) Prevents infrared rays reflected from Earth from escaping Earth’s atmosphere
(C) Prevents ultraviolet rays from the sun
(D) Reflects back radio waves