Question

It is easier to determine the electron configurations for the p-block elements in periods 1, 2, and 3 than to determine the electron configurations for the rest of the p-block elements in the periodic table because
a.they have a larger number of core electrons.
b.their electrons are assigned to s and p orbitals only.
c.their electrons are placed in a higher number of orbitals.
d.they have more valence electrons available for bonding.

Answer 1

I am pretty sure the answer would be b

Answer 2

Answer:

b.their electrons are assigned to s and p orbitals only.

Explanation:

Electron configuration of He, B and Al the elements that lie in the first, second and third period of the periodic table respectively as follows:

He:  1s²

B:  [He] 2s² 2p¹

Al:  [Ne] 3s² 3p¹

Ga:  [Ar] 3d¹⁰ 4s²  4p¹

In Ga, element ling in the 4th period, electrons enter the s, p and d orbitals.  So before assigning electrons to the p orbitals it is important to ensure that the d orbital is  either partially or fully filled.