76. In the reaction Fe 2 O 3 +3CO 2Fe+3CO.
Ans (a) CO acts as a reducing agent
77. Which of the following are present in a dilute aqueous solution of hydrochloric acid?
Ans (a) H 3 O^ – +Cl^ –
78. Which of the following is acidic in nature?
Ans (a) Lime juice
79. The chemical formula for the plaster of Paris is:
Ans (c) CaSO4.1/2HO
80. An aqueous solution turns red litmus solution blue. Excess addition of which of the following would reverse the change?
Ans (d) Hydrochloric acid
81. Write the products formed when aluminium metal is heated with manganese dioxide:
Ans (d) Mn + A*l_{2}*O_{3}
82. Pick out the chemically most reactive element from the given triads:
Ans (c) K and F
83. Which of the following compounds can not exhibit chain isomerism?
Ans (a) Propane
84. Name the functional group present in CH3 CO CH3
Ans (c) Ketone
85. The properties of eka-aluminium predicted by Mendeleev are the same as the properties of a later discovered elements:
Ans (c) Gallium
86. Orange-coloured photosynthetic pigment is:
Ans (a) Carotene
87. Double fertilization is a unique feature of:
Ans (c) Angiosperms
88. Back cross is a cross between:
Ans (d) F 1 * Any parent
89. Haemophilia disease is linked with:
Ans (a) Sex chromosome
90. Which one of these is haploid?
Ans (b) gametes