The outermost electronic configuration of the most electronegative element is :

1. ns²np³

2. ns²np⁴

3. ns²np⁵

4. ns²np⁶

The electronegativity of the following elements increases in the order of:

Allred Rochow's scale is related to:
 

1. Electronegativity, radius, and Z^*

2. Resonance energy of the molecule, ionisation potential and electron affinity.

3. Bond Polarity, diagonal relationship and periodicity.

4. None of the above.

Aqueous solutions of two compounds $M_1-O-H<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>M_2-O-H$ are prepared in two different beakers. If, the electronegativity of $M_1=3.4<mspace\; width="1em"></mspace>,<mspace\; width="1em"></mspace>M_2=1.2,<mspace\; width="1em"></mspace>O=3.5<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>H=2.1,$ then the nature of two solutions will be respectively:

(a) acidic, basic             (b) acidic, acidic

(c) basic, acidic             (d) basic, basic