12th class (Fsc) Chemistry unit 4 MCQs
76. Which element is most electonegative after fluorine?
a. Nitrogen
b. Phosphorous
c. Sulphur
d. Oxygen
77. Those metals which reacts with cold dilute H2SO4 and librate hydrogen are:
a. Zn,Mg,Hg
b. Fe,Zn,Cu
c. Fe,Sn,Ag
d. Sn,Mg,Fe
78. Te has two allotropic forms:
a. Flint and quartz
b. Metallic and non metallic
c. A And b
d. Red and gray
79. H2SO4 reacts with SO3 to form:
a. H2S2O6
b. Vitriol
c. SO2
d. Oleum
80. H2SO4 acts as:
a. Oxidizing agent
b. Reducing agent
c. Dehydrating agent
d. Both a and b
81. In contact process which of the following is used as arsenic purifier:
a. FeSO4
b. Fe(OH)2
c. Fe(SO4)3
d. Fe(OH)3
82. …… is used in storage cell and electrical battery:
a. H3PO4
b. H2SO4
c. HMPO3
d. Oleum
83. H2SO4 was 1st prepared by:
a. Moseley
b. Jabir Bin Hayyan
c. Al Razi
d. None of these
84. What is the action of cold concentration H2SO4 on metals like Cu,Ag,Hg,Pb,Au?
a. Does not react
b. Reacts vigorously
c. Reacts on heating
d. Reacts moderately
85. Which one of the following pairs does not reacts with H2SO4 at all:
a. Pb,Cu
b. Zn,Fe
c. Au,Pt
d. Sn,Mg
86. The element which evolves two gases with conc. H2SO4 is:
a. S
b. Si
c. P
d. C
87. Anhydride of sulphuric acid is:
a. H2S2O3
b. SO2
c. H2SO3
d. SO3
88. Which of the following acts as pickling agent:
a. HCL
b. HNO3
c. HNO2
d. H2SO4
89. SO3 is not absorbed in water directly to form H2SO4 , because:
a. Reaction is exothermic
b. Reaction does not go completion
c. SO3 is insoluble in water
d. Reaction is quite slow
90. Glucose and can sugar becomes black when cone. H2SO4 is added to it. The function of H2SO4 is:
a. Dehydrating agent
b. Oxidizing agent
c. Carbonating agent
d. Reducing agent
91. Sulphuric acid can not be used as:
a. Sulphonating agent
b. Hygroscopic agent
c. Efflorescent
d. Oxidizing agent
92. The gas which cannot be dried by con. H2SO4 :
a. NO2
b. SO2
c. HCI
d. NH3
93. Sulphuric acid is a dibasic acid because:
a. H2SO4 is acid as well as dehydrating agent
b. Each molecule produces two H+ ions
c. It gives two OH– ion
d. None of these
94. Out of all the elements of group VA. the highest ionization energy is possessed by:
a. Sb
b. N
c. Bi
d. P
95. Among group VA elements, the most electro negative element is:
a. P
b. Sb
c. As
d. N
96. Oxidation of NO in air produces:
a. N2O4
b. N2O
c. N2O5
d. N2O3
97. The brown gas formed, when metal reduces HNO3 to:
a. NO2
b. N2O5
c. NO3
d. N2O3
98. Laughing gas is chemically:
a. NO
b. NO2
c. N2O4
d. N2O
99. Out of all element os group VIA, the highest melting point and boiling point is shown by the element:
a. S
b. Te
c. Po
d. Se
100. SO3 is not absorbed in water directly to form H2SO4 because:
a. The reaction is highly exothermic
b. The reaction does not go to completion
c. SO3 is insoluble in water
d. The reaction is quite slow