12th class (Fsc) Chemistry unit 16 MCQs
101. The acid rain water has pH:
a. Between 5 and 7
b. Below 5
c. Between 7 and 14
d. 7
102. In contact process of manufacturing sulphuric acid, sulphur trioxide is not absorbed in water because:
a. The reaction is quite slow
b. The reaction is highly exothermic
c. The reaction does not go to completion
d. None of these
103.In modern Haber process plants, the temperature maintained during the process is:
a. 370-470 K (100o -200o )
b. 670-770 K (400o -500o )
c. 570-600 K (300o -380o )
d. 270-370 K (0o – 1000 )
104. In the haber process for manufacturing of ammonia, nitrogen is taken from:
a. Minerals containing nitrates
b. Ammonium salts obtained industrially
c. Proteins occurring in living bodies
d. Air
105. The nature of an aqueous solution of ammonia is:
a. Acidic
b. Amphoteric
c. Basic
d. Neutral
106. Unpolluted rain water has a pH of:
a. 5.6
b. 4.9
c. 7.0
d. 5.3
107. The catalyst used in Habeas process is:
a. Silicon oxide
b. Magnesium oxide
c. Aluminium oxide
d. None of these
108. Which one of the following is correct equation of 1st ionization of sulphuric acid?
a. H2SO4(aq) + H2O(I) → 2H+SO4
b. H2SO4(aq) + H2O(I) → 2H+SO42-
c. H2SO4(aq) + H2O(I) → 2H O+SO42
d. H2SO4(aq) + H2O(I) → H+SO4
109. Which one the following is correct chemical reactions for ammonia formation by Haber process?
a. 2N(g)+3H2 (g) → 2NH(g)
b. N2 (g)+3H2 (g) → 2NH3 (g)
c. N2 (g)+3H2 (g) → 2NH3 ???????(g)
d. 2N(g)+3H2 (g) → 2NH3 (g)
110. The pH of acid rain is:
a. Below 5
b. 7
c. Between 7 and 14
d. Between 5 and 7
111. Which one of the following products is obtained where sulphur trioxide is absorbed in concentrated sulphuric acid?
a. Hydrogen sulphide
b. Oleum
c. Sulphate
d. Aqua regia
112. About 80% of ammonia is used for the production of:
a. Nyton
b. Explosives
c. Polymers
d. Fertilizers
113. Urea is the most widely used nitrogen fertilizer in Pakistan, Its composition is:
a. N2H4CO2
b. NH2CO
c. N2H5CO2
d. None of these
114. During the manufacturing of nitric acid. nitric oxide is oxidized to nitrogen dioxide, This reaction is given as: 2NO(g)+O2 ⇌ NO2 (g) △H=-114Kj/mol according to Le chateliers’s principle
a. Reaction must be carried out at low temperature
b. Reaction must not be temperature dependent
c. Reaction must be carried out at high temperature
d. Reaction must be carried out at room temperature
115. What is the percentage of nitrogen in NH3 NO3 ?
a. 20%
b. 65%
c. 58%
d. 35%
116. The %gae of nitrogen in ammonium nitrate is:
a. 33%
b. 46%
c. 13%
d. 82%
117. Which one of the following is anhydride of sylphuric acid?
a. Iron pyrite
b. Sulphur (ii) oxide
c. Sulphur (VI) oxide
d. Sulphur (vi) oxide
118. During contact process of H2SO4 synthesis, the following reaction occurs. 2SO4 (g) +O2 (g) → 2SO3 (g) △H=-96 KJmol-1
a. Temperature is raised to very high degree
b. SO3 formed is reemoved very quickly
c. Both temperature and pressure are very low
d. None of these
119. Synthesis of ammonia by haber’s process is a reversible reaction. what should be done to increase the yield of ammonia in the following reaction? 2N2 (g) +3H2 (g) ⇌ 2NH3 (g) △H=-92kj/mol-1
a. Pressure should be increases
b. Pressure should be decreased
c. Concentration of nitrogen should be decreased
d. Ammonia should remain in reaction mixture
120. The suspected liver carcinogen which aslo has negative reproduction and development effect on human is:
a. Tropoform
b. Iodoform
c. Chloroform
d. Bromoform
121. The increase in concentration of oxidizing agents in smog like H2 O2 ,HNO3 ,PAN and ozone in the air is called:
a. Photochemical smog
b. Carbonated smog
c. Sulphonated smog
d. Nitrated smog
122. Which is the metal, whose elevated concentration is harmful for fish as it clogs the gills thus causing suffocation?
a. Zinc
b. Sodium
c. Aluminium
d. Lead
123. Aerobic decomposition of organic matter i.e glucose by bacteria in water sediments produces:
a. Methane
b. Propene
c. Butane
d. Ethane
124. The yellowish-brown color in photochemical smog is due to the presence of:
a. Carbon monoxide
b. Sulphur dioxide
c. Nitrogen dioxide
d. Carbon dioxide
125. …… is an eye irritant:
a. Peroxymethoxy aniline
b. Peroxyacetyl mitrate
c. Peroxyacetyl anilne
d. Peroxyacetyl nitrite
126. Which of the following pollutants can of red blood cells?
a. Carbon monoxide
b. Chlorofluorocarbons
c. Oxides of nitrogen
d. Oxides of sulphur
127. The biggesnt source of acid rain is the oxide of:
a. O
b. N
c. C
d. S
128. Burning of which one of the following waste is considered as useful industrial fuel or to produce electricity.
a. Paper
b. Metals
c. Plastic
d. Grass
129. Ozone concentration is measured in:
a. Debacle units
b. Debye units
c. Dobson unit
d. Dupont units
130. The gas which is mainly produced in landfill from the waste is:
a. SO2
b. CH4
c. CI2
d. CO2