1. K+,Cl-,Mg2+,Sc3+
2. Na+,Ca2+,Sc3+,F-
3. K+,Ca2+,Sc3+,Cl-
4. Na+,Mg2+,Al3+,Cl-
K+,Ca2+,Sc3+,Cl-
1. Dobereiner
2. Mendeleev
3. Robert Boyle
4. Prout
Prout
1. 1
2. 2
3. 3
4. 4
3
1. Atomic size
2. Negative electron gain enthalpy
3. Ionisation enthalpy
4. None of these
Atomic size
1. AI
2. AI3+
3. mg2+
4. Mg
AI3+
1. Ionization enthalpy
2. Solubility of their hydroxides
3. Solubility of their sulphates
4. Electronegativity
Solubility of their hydroxides
1. High ionization enthalpy
2. Low ionization enthalpy
3. Stable electronic configuration
4. None of these
Low ionization enthalpy
1. Ionization enthalpy increases for each successive electron
2. The greater increase in ionization enthalpy is experienced on removal of electron from core noble gas configuration
3. End of valence electrons is marked by a big jump in ionization enthalpy
4. Removal of electron from orbitals bearing lower n value is easier than from orbital having higher n value
Removal of electron from orbitals bearing lower n value is easier than from orbital having higher n value
1. Pauling
2. Mulliken-Jaffe
3. Allred-Rochow
4. All of the these
All of the these
1. Facilitate systematic study of element and their compounds
2. Rationalize known chemical facts about element
3. Predict new element
4. All of the these
All of the these