Assertion: The atomic radii of calcium is smaller than sodium
Reason: Calcuim has a lower nuclear charge than sodium.

The atomic size of beryllium is smaller than the atomic size of lithium. Give reason.

Assertion : Atomic mass of calcium is 40 u Reason : An atom of calcium is 40 times heavier than an atom of carbon with mass 12 u.

Assertion : Gallium has smaller atomic size than aluminium Reason : Because of greater nuclear attraction due to poor shielding effect of outer shell electrons from the nucleus by the d-electrons

Assertion : -I effect of Cl atom is greater than F atom. Reason : Cl atom has more elctronegativity than F atom.

Assertion :- I effect of Cl atom is greater than F atom. Reason :- Cl atom has more elctronegativity than F atom.

Assertion: The atomic radii of the elements of the oxygen family are smaller than the atomic radii of corresponding elements of the nitrogen family. Reason: The members of the oxygen family are more electronegative because they have lower values of nuclear charge, than those of the nitrogen family.

The atomic size of lithium is ________ than that of sodium. (greater/smaller).

Sodium has higher density than Lithium, but potassium has lower density than sodium. Why?