Question

Can someone please help me with this? The question is in the picture

Answer 1

For question (a) the order of increasing ionic radius is:
`\[ Ra^(2+) < Sr^(2+) < Ba^(2+) < Mg^(2+) < Be^(2+) \]` . For question (b) the complete order for increasing ionic radius is:
`\[ Al^(3+) < Mg^(2+) < Na^(+) < Cl^(-) < S^(2-) < P^(3-) \]`

a) Ba²⁺, Mg²⁺, Sr²⁺, Ra²⁺, Be²⁺:

Ionic radius generally decreases as you move across a period from left to right and increases as you move down a group. This is because as you move across a period, the effective nuclear charge increases, pulling the electrons closer to the nucleus.

In contrast, moving down a group adds energy levels, resulting in larger ionic radii.

In this case, we're comparing ions with the same charge
`(\(+2\))`, so the size of the ions will mainly depend on the number of energy levels.

So, the order of increasing ionic radius is:

`\[ Ra^(2+) < Sr^(2+) < Ba^(2+) < Mg^(2+) < Be^(2+) \]`

b) Cl⁻¹, Mg²⁺, Na⁺¹, P³⁻, Al³⁺, S²⁻:

For ions with different charges, you need to consider both the effect of the charge and the number of energy levels.

1. Consider the charge:

- For a given ion, as the charge increases, the ionic radius generally decreases (more charge pulls the electrons in closer).

- For a given ion with different charges, the higher charge corresponds to a smaller ionic radius.

2. Consider the number of energy levels:

- For ions with the same charge, more energy levels generally result in a larger ionic radius.

Based on these principles, the order of increasing ionic radius is:

`\[ Al^(3+) < Mg^(2+) < Na^(+) < Cl^(-) < S^(2-) < P^(3-) \]`

So, the complete order for increasing ionic radius is:

`\[ Al^(3+) < Mg^(2+) < Na^(+) < Cl^(-) < S^(2-) < P^(3-) \]`