The basic difference between Mendeleev’s Periodic Law (A) and Modern Periodic Law (B) is
1. A is based on atomic weights while B is based on atomic numbers.
2. B is based on atomic weights while A is based on atomic numbers.
3. A is based on the number of isotopes while B is based on atomic numbers.
4. A is based on physical properties while B is based on chemical properties.
The formula for the oxide formed by Eka-aluminum is:
The basic theme of the periodic table is
1. To classify the elements in a period according to their properties.
2. To classify the elements in a group according to their ionization enthalpy.
3. To classify the elements in periods and groups according to their properties.
4. To classify the elements in periods and groups according to their lustre.
Those in a group that falls under the law of triads include:
1. Cl, Br, I
2. C, N, O
3. Na, K, Rb
4. H, O, N
Eka aluminium and Eka silicon are now known as:
1. Ga and Ge
2. Al and Si
3. Fe and S
4. H+ and Si
An example of metalloid elements in the periodic table is:
1. Na and K
2. Cu and Al
3. As and Si
4. Ca and Mg
In the long form of the periodic table, all the non-metals are placed under:
The element named after Lawrence Berkeley Laboratory is
Among the following elements whose atomic numbers are given below, which cannot be accommodated in the present set up of the long periodic table?
Among the following elements, the one that is not an actinoid is:
1. Curium (Z=96)
2. Californium (Z=98)
3. Uranium (Z=92)
4. Terbium (Z=65)