Calculate the effective nuclear charge experienced by the valence electrons of chlorine.

$Z_{\text{e}\text{f}\text{f}}=$

Calculate the effective nuclear charge experienced by the valence electrons of aluminum.

Describe how the difference in $Z_{\text{e}\text{f}\text{f}}$ between these two elements predicts their relative atomic radii.

Chlorine has a larger atomic radius than aluminum because chlorine has a larger effective nuclear charge.

Aluminum has a smaller atomic radius than chlorine because aluminum has a larger effective nuclear charge.

Aluminum has a larger atomic radius than chlorine because aluminum has a larger effective nuclear charge.

Chlorine has a smaller atomic radius than aluminum because chlorine has a larger effective nuclear charge.