When sodium is converted into sodium ion (Na⁺) then the effective nuclear charge of sodium (Na) is:

1. Increases 3 times approximately 

2. Increases 2 times approximately 

3. Decreases 2 times approximately 

4. Decreases 3 times approximately 

If Z_eff of element having atomic number 11 is 2.2, then Z_eff of elements having atomic number 12 and atomic number 20 are respectively :-

1. 2.85, 3.92

2. 3.92, 2.85

3. 2.2, 2.2

4. None of the above