Based on the reactivities of the elements involved, which reactions will form products that are more stable than the reactants? 2lif + cl2 → 2licl + f2 2lii + cl2 → 2licl + i2 2licl + br2 → 2libr + cl2 2libr + f2 → 2lif + br2 2libr + i2 → 2lii + br2

2 LiI + Cl₂ → 2 LiCl + I₂

2 LiBr + F₂ → 2 LiF + Br₂

Explanation

Each of the five reactions involve one halogen molecule (F₂, Cl₂, Br₂, and I₂) substituting the ion of another halogen (F⁻, Cl⁻, Br⁻, and I⁻).

Halogen atoms are found in group 17 of the periodic table. They are all non-metal elements. Each of the halogen atom will gain one electron to form an ion of charge -1. However, the tendency to do so decreases down the group.

F is the first halogen in group 17. It has only two shells of electrons. Cl is right under F. Its electrons occupy three main energy shells. Br follows with four main energy shells. I is under Br and has five main energy shells.

Atoms of all four elements have the same effective nuclear charge of +7. However, F has the smallest radius. As a result, it has the strongest hold on electrons around it. Its ion F⁻ is more stable than ions of Cl, Br, or I. Similarly, its molecule F₂ is more reactive than Cl₂, Br₂, and I₂.

As a result, the stability of halogen molecules increases down the group:

Stability: F₂ < Cl₂ < Br₂ < I₂.

The stability of halogen ions decreases down the group:

Stability: F⁻ > Cl⁻ > Br⁻ > I⁻.

Cl₂ repaces F⁻ (from LiF) in first reaction. F₂ and Cl⁻ are produced. F₂ is less stable than Cl₂. Cl⁻ is less stable than F⁻.

Cl₂ replaces I⁻ (from LiI) in the second reaction. I₂ and Cl⁻ are produced. I₂ is more stable than Cl₂. Cl⁻ is more stable than I⁻.

Br₂ replaces Cl⁻ (from LiCl) in the third reaction. Cl₂ and Br⁻ are produced. Cl₂ is less stable than Br₂. Br⁻ is less stable than Cl⁻.

F₂ replaces Br⁻ (from LiBr) in the fourth reaction. Br₂ and F⁻ are produced. Br₂ is more stable than F₂. F⁻ is more stable than Br⁻.

I₂ replaces Br⁻ (from LiBr) in the fifth reaction. Br₂ and I⁻ are produced. Br₂ is less stable than I₂. I⁻ is less stable than Br⁻.

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I’m not sure what your trying to say here.. can you clarify again?