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Describe the ammonium ion, NH4+, and the sulfate ion, SO42-. What compounds would these ions form with potassium and fluoride ions? Write the formula units for the resulting compounds.

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Answer:

- NH₄F (ammonium fluoride)

- K₂SO₄ (potassium sulfate)

Step-by-step explanation:

Ammonium is a ion which is formed, when the ammonia takes a proton, from water. It's the conjugate strong acid, for the ammonia, which is a weak base.

This is the equilibrium

NH₄ ⇄ NH₃ + OH⁻

In the ammoniumm, N has 4 covalents bonds.

When ammonium reacts with F⁻, it forms this salt

NH₄⁺ + F⁻ → NH₄F

It can't be an equilibrium because the F⁻, is the conjugate weak base from the strong acid HF and it doesn't react. The ammonium fluoride is a ionic salt, which is completely soluble in water.

Sulfate ion is generated when the sulfuric acid is deprotonated. It's a weak acid when the first proton is released and so it forms bisulfate ion. This reaction has a litle Ka.

When this bisulfate ion is deprotonated again, it forms the sulfate ion.

Generally, the H₂SO₄ is treated as a strong acid.

The equations are this:

H₂SO₄ ⇄ H⁺ + HSO₄⁻ Ka

HSO₄⁻ → H⁺ + SO₄⁻²

As the sulfate has released 2 H⁺, when it reacts with K⁺, it forms also a ionic salt.

In this case there are 2 moles of K⁺.

K⁺ is the conjugate weak acid that comes, from a strong base (KOH)

It doens't react.

2K⁺ + SO₄⁻² → K₂SO₄

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