121. | Which of the following is the best conductor of heat |
A. alcohol | |
B. Parad | |
C. ether | |
D. Water |
122. | Which element was first produced artificially? |
A. neptunium | |
B. plutonium | |
C. francium | |
D. technetium |
123. | What is ultimately formed as a result of radioactive electrolysis of uranium? |
A. radium | |
B. thorium | |
C. polonium | |
D. lead |
124. | Brass gets discolored in air due to continuous presence of |
A. aluminum phosphide | |
B. hydrogen sulfide | |
C. hydrogen vapor | |
D. aluminum sulfide |
125. | The red color of ruby is due to the presence of |
A. chromium oxide | |
B. calcium oxide | |
C. iron oxide | |
D. zinc oxide |
126. | Glass is |
A. supersaturated solid | |
B. Super absorbed liquid | |
C. superheated gas | |
D. Supersaturated liquid |
127. | Which of the following is called Yashad Pushpa |
A. zinc chloride | |
B. zinc oxide | |
C. zinc nitrate | |
D. zinc bromide |
128. | Which of the following is responsible for making Pyrex glass more durable? |
A. potassium carbonate | |
B. lead oxide | |
C. borax | |
D. ferric oxide |
129. | What type of glass is used to make glass reinforced plastic |
A. pyrex glass | |
B. flint glass | |
C. quartz glass | |
D. fiberglass |
130. | Photochromatic glass has the property of having black color due to the presence of |
A. silver bromide | |
B. silver oxide | |
C. silver nitrate | |
D. silver chloride |