| 171. | What is called heavy when it is in water |
A. heavy isotope of hydrogen | |
B. heavy isotope of oxygen | |
C. Atomic number of hydrogen atom ` | |
D. atomic number of oxygen atom |
| 172. | heavy water |
A. is the coolant | |
B. is retarder | |
C. ore is | |
D. have fuel |
| 173. | used in bleaching hair |
A. sulfuric acid | |
B. oxalic acid | |
C. hydrogen peroxide | |
D. heavy water |
| 174. | Used to revive the colors of old oil paintings |
A. sulfuric acid | |
B. oxalic acid | |
C. hydrogen peroxide | |
D. heavy water |
| 175. | carbon is a |
A. Metal | |
B. nonmetal | |
C. Metalloid | |
D. compound |
| 176. | The essential basic element of all organic compounds is |
A. nitrogen | |
B. oxygen | |
C. Carbon | |
D. sulfur |
| 177. | carbon atoms contain |
A. 6e, 6p and 12n | |
B. 6e, 6p and 6n | |
C. 6e, 12p and 6n | |
D. 12e, 6p and 6n |
| 178. | Which of the following elements forms the largest number of compounds with hydrogen? |
A. oxygen | |
B. nitrogen | |
C. Carbon | |
D. silicone |
| 179. | Different forms of the same element are called |
A. minus ion | |
B. money ion | |
C. buffer | |
D. misshapen |
| 180. | The property due to which the same element is found in many forms is called |
A. polymerization | |
B. burdensome | |
C. isotopes | |
D. abnormality |