51). The high-temperature superconductors are :
| A). metal alloys |
| B). ceramic oxides |
| C). inorganic polymers |
| D). pure rare earth metals |
|
52). The variety of coal in which the deposit contains recognisable traces of the original plant material is :
| A). anthracite |
| B). lignite |
| C). peat |
| D). bitumen |
|
53). The highest grade of coal whose surface is shining and has the highest calorific value, is :
| A). Bituminous |
| B). Lignite |
| C). Anthracite |
| D). Peat |
|
54). Diamond is the harder than graphite because of :
| A). difference of layers of atoms |
| B). tetrahedral structure of diamond |
| C). difference of crystalline structures |
| D). none of these |
|
55). Radioactive disintegration of uranium ultimately results in formation of :
| A). radium |
| B). thorium |
| C). polonium |
| D). lead |
|
56). The isotope of uranium capable of sustaining chain reactions is :
| A). U-235 |
| B). U-238 |
| C). U-239 |
| D). none of these |
|
57). No two electrons I an atom can have the same set of four quantum number' is:
| A). Bohr's law |
| B). Aufbau principle |
| C). Newton's law |
| D). Pauli's exclusion principle |
|
58). The location and energy of an electron in an atom can be specified by :
| A). atomic mass |
| B). atomic number |
| C). quantum numbers |
| D). None of these |
|
59). Atoms of an element differ from those of all other elements in :
| A). atomic number and electronic configuration |
| B). atomic number and number of valance electrons |
| C). number of neutrons and electronic configuration |
| D). number of neutrons and number of valence electrons |
|
60). Match the following:
Particle Charge
A. a Particle 1. + 2e
B. B Particle 2. - e
C. Neutron 3. Zero
D. Proton 4. + e
Below options are given in A B C D order.
| A). 1 2 3 4 |
| B). 2 4 3 1 |
| C). 3 2 1 4 |
| D). 4 3 2 1 |
|
