NEETChemistrys Block Elements
Which statement best explains why the atomic and ionic radii of alkaline earth metals are smaller than those of the corresponding alkali metals in the same periods?
Options
- AAlkaline earth metals have more electrons than alkali metals.
- BAlkaline earth metals have a higher nuclear charge than alkali metals.
- CAlkaline earth metals have a higher electron affinity than alkali metals.
- DAlkaline earth metals have a lower ionization energy than alkali metals.
Correct answer
B. Alkaline earth metals have a higher nuclear charge than alkali metals.
Step-by-step solution
The atomic and ionic radii are determined by the balance between the attractive force of the nucleus and the repulsive force between electrons. Alkaline earth metals have more protons in their nuclei compared to alkali metals, leading to a stronger nuclear charge and smaller atomic/ionic radii.